Load absorbing device for use with a vehicle seat, vehicle occupant protection system using such a device and method of operating the system
By using guide rails and strips in the vehicle seats to absorb inertial energy, the increased risk of reclining seating positions in accidents is mitigated, thus achieving effective protection for occupants.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- AUTOLIV DEV AB
- Filing Date
- 2024-11-13
- Publication Date
- 2026-05-29
AI Technical Summary
In the event of a vehicle accident, occupants in a reclined seating position may experience high head acceleration and neck extension due to the lack of head restraint airbag protection, increasing the risk of slippage and increasing spinal forces and acceleration in the pelvic region, thus increasing the risk of pelvic and lumbar spine fractures.
A load-absorbing device is designed, including upper and lower guide rails and a strip connected therebetween. The strip deforms as it slides between the guide rails to absorb energy. It gradually increases its cross-sectional area through a tapered section to absorb inertial energy. Combined with a locking arrangement, it allows the guide rails to shift when needed, and uses the inertial energy of a vehicle collision to slide the seat to a normal sitting position.
It effectively absorbs inertial energy during a collision, reduces the risk of skidding, minimizes forces on the spine and pelvis, and protects occupant safety.
Smart Images
Figure CN122122037A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a load-absorbing device for use with a vehicle seat, a vehicle occupant protection system using such a device, and a method of operating a vehicle occupant protection system in a vehicle. Background Technology
[0002] In recent years, automation in vehicle operation has increased significantly. However, historically, the driver's role was entirely to operate the vehicle. Modern vehicles include an increasing number of electronic systems that assist the driver while operating the vehicle, or even completely free the driver by providing autonomous driving capabilities. In some situations, the driver is even superfluous. In such scenarios, the driver can adopt a seating position different from the conventional driving position required for direct driver operation. This development allows drivers to adopt a more rearward and even more reclined position. The driver can even lie down. This has been extended to other occupants. However, in the event of an accident, a more reclined position can indeed pose a problem, as those conventionally seated and wearing seatbelts are protected by seatbelts and one or more airbags.
[0003] Therefore, a reclined seating position can introduce potentially adverse interactions between the seated person and the surrounding restraint system (i.e., the lumbar belt and seat floor). Examples of adverse interactions seen in a fully reclined position include high head acceleration and neck extension due to the absence of a head restraint airbag. Another example is the increased risk of slippage. Furthermore, there is increased spinal force and increased acceleration where the pelvic region contacts the seat floor. The latter leads to an overall increased risk of pelvic and lumbar spine fractures. Studies have found that one way to reduce load on the pelvis and lumbar spine is to incorporate a load-limiting system into the seat that operates in the x-direction and / or z-direction of the vehicle. Summary of the Invention
[0004] The object of the present invention is to provide a load-absorbing device for use with vehicle seats.
[0005] Load absorption devices should be adaptable to different external parameters, such as vehicle speed, seat back tilt, and occupant weight.
[0006] The load absorption device should allow for easy adaptation to different vehicle types, intended uses of the vehicle, types of seats in the vehicle, and different seat designs.
[0007] These and other objectives, which are apparent from the following overview and description, are achieved by the load-absorbing device according to the appended claims.
[0008] According to one aspect of the present invention, a load-absorbing device for use with a vehicle seat is provided, the device comprising:
[0009] A guide rail arrangement including an upper guide rail and a lower guide rail, the upper guide rail being configured to connect to the lower side of the vehicle seat, and the lower guide rail being configured to be fixedly connected to the top surface of the vehicle floor; wherein the upper guide rail and the lower guide rail are slidably connected to each other to allow longitudinal displacement between the upper guide rail and the lower guide rail; and
[0010] A strip having: a first leg having a first end, a second leg having a second end, and a curved portion between the first leg and the second leg, wherein the first end is fixedly connected to the lower guide rail, and the second end is fixedly connected to the upper guide rail; wherein
[0011] The curved portion is configured to translate in the same direction as the upper guide rail during the mutual displacement between the upper and lower guide rails.
[0012] Therefore, a load-absorbing device is provided in which energy is absorbed by deforming a strip arranged in a finite gap between two parallel guide rails. In the event of a collision that causes the occupant to move forward, the upper and lower guide rails are displaced relative to each other due to the inertial energy of the seat and / or the seated occupant. The strip is oriented between the two guide rails such that the curved portion is configured to translate along the strip in the same direction as the upper guide rail during the mutual displacement between the upper and lower guide rails. This means that the two fixed ends of the strip will be forced toward each other by linear translation. During this translation, the relative lengths of the first and second legs will change, i.e., one leg will be shorter and the other longer. However, the strip in this manner does not substantially elongate. In addition, the radius in the curved portion will remain substantially the same throughout the translation. This allows for effective absorption of inertial energy from the seat and the seated occupant during a collision. When used in a vehicle seat, there will be a reduced risk of skidding and additionally reduced forces on the spine and pelvic region.
[0013] During the vehicle design phase, the characteristics of the strips can be adapted based on parameters such as vehicle type, seat type, expected seating position during normal use, and expected weight of average seat occupants. Non-limiting examples of adaptable strip characteristics include the type of material in the strip, such as tensile strength and the cross-sectional area of the strip as seen transversely to its longitudinal extension. Therefore, all seats in one and the same vehicle can be equipped with load-absorbing devices, but each device can be fitted with different strip designs.
[0014] The convex portion of the curved section can form a leading edge during the mutual displacement between the upper and lower guide rails.
[0015] The first or second leg may include a tapered portion that tapers in the direction toward the curved portion along its longitudinal extension.
[0016] As the curved section is forced to translate along the tapered longitudinal extension of the strip's leg toward the relatively wider portion of the strip (i.e., toward the strip's larger cross-sectional area), energy consumption and thus load absorption gradually increase. In other words, as the strip's cross-sectional area gradually increases, more energy is required to reshape the strip during the translation of the curved section.
[0017] The taper angle can be adapted during the vehicle design phase according to the intended use of the energy absorption device. A larger taper angle results in more gradual load absorption. Therefore, the strip can be configured with a desired load absorption profile suitable for specific design criteria. As a non-limiting example illustrating this principle: a low taper angle (e.g., 1-10 degrees) may be advantageous in applications where the collision involves relatively low inertial forces or where the expected weight of the seat occupant (such as a child) is relatively low. Conversely, a higher taper angle (e.g., 10-30 degrees) may be advantageous in applications where the collision involves relatively high inertial forces or where the expected weight of the seat occupant corresponds to 50% of an adult. By providing two consecutive taper sections with different angles, a strip capable of meeting both conditions can be provided.
[0018] As can be seen under normal operating conditions of the load-absorbing device, the tapered portion is preferably arranged adjacent to the curved portion. In the context of this invention, "normal operating conditions" should be understood as conditions under which the load-absorbing device is not subjected to impact.
[0019] The tapered portion can have the same degree of tapering along the two opposite longitudinally extending edges of the strip. Therefore, the tapering degree can be symmetrical along the opposite sides.
[0020] The tapered portion may have a gradually increasing cross-sectional area. The tapered portion may have a straight longitudinal extension. Those skilled in the art will recognize that other geometries, such as a single curved longitudinal extension, can be used. As seen relative to the longitudinal centerline of the strip, the single curved extension is preferably concave. In yet another embodiment, the strip may have a stepped construction with a gradually increasing cross-sectional area along its longitudinal extension.
[0021] The tapered portion may have a first tapered portion and a second tapered portion, the first tapered portion having a first tapered angle relative to the longitudinal centerline of the strip, and the second tapered portion having a second tapered angle relative to the longitudinal centerline of the strip, wherein the second tapered angle is greater than the first tapered angle.
[0022] The taper angle can be adapted during the vehicle design phase according to the intended use of the energy absorption device. A larger taper angle results in more gradual load absorption. Therefore, the strip can be configured with a desired load absorption profile suitable for specific design criteria. As a non-limiting example illustrating this principle: a low taper angle (e.g., 1-10 degrees) may be advantageous in applications where the collision involves relatively low inertial forces or where the expected weight of the seat occupant (such as a child) is relatively low. Conversely, a higher taper angle (e.g., 10-30 degrees) may be advantageous in applications where the collision involves relatively high inertial forces or where the expected weight of the seat occupant corresponds to 50% of an adult. By providing two consecutive taper sections with different angles, a strip capable of meeting both conditions can be provided.
[0023] The load absorption device may also include a locking arrangement configured to selectively interlock the upper and lower guide rails. The locking arrangement may include an electromechanical unlocking element, an electromagnetic unlocking element, or a pyrotechnic unlocking element. The locking arrangement may be in the form of a locking pin that engages the upper and lower guide rails and is pulled out / pulled out of the locking engagement by means of the unlocking element.
[0024] The locking arrangement can be configured to communicate with the vehicle's ECU (Electrical Control Unit). By default, the locking arrangement is preferably set to the locked position during normal vehicle operation. This prevents the rails from shifting relative to each other during normal vehicle operation. If the ECU's processor determines, based on signals from the collision sensor elements, that an impending or ongoing vehicle collision exists and the seating position sensor elements indicate that the seating is set in a specific position where there is a risk of skidding, the ECU will instruct the locking arrangement to unlock. This allows the rails to shift relative to each other, thereby allowing load absorption by the strips. Another parameter that can be used as an input to the ECU to determine whether the locking arrangement should be unlocked is the vehicle's speed. If the speed is below a certain threshold, the load from the accident will therefore be handled by other safety systems in the vehicle.
[0025] According to another aspect of the present invention, a vehicle occupant protection system is provided. The vehicle occupant protection system includes:
[0026] Vehicle seats, which are configured to accommodate occupants;
[0027] The load-absorbing device according to any one of claims 1 to 8, wherein the guide rail arrangement is configured to connect the vehicle seat to the vehicle floor;
[0028] A locking arrangement configured to selectively lock the vehicle seat in a defined seating position to prevent relative displacement between the rails in the rail arrangement when locked, and to allow displacement between the rails in the rail arrangement when unlocked.
[0029] Collision sensor element, the collision sensor element being adapted to determine an impending or ongoing vehicle collision; and
[0030] A seating position sensor element adapted to determine a seating position;
[0031] When it is determined that a guide rail in the guide rail arrangement has shifted to a position where the seat is set in a rear-facing position and a vehicle collision is imminent or ongoing, the locking arrangement is configured to be unlocked, thereby allowing mutual displacement between the guide rails and thereby allowing the seat to slide from the rear-facing position toward a normal driving position; and
[0032] Thus, the sliding of the seat from the rearward seating position toward the conventional driving seating position is performed by using the inertial energy from the vehicle collision, while the strip is forcibly deformed and thereby absorbs the inertial energy of the seat and / or the seated occupant.
[0033] In the context of this invention, the term "normal driving seating position" should be understood as the intended normal seating position designed for seat belt and airbag systems in a vehicle.
[0034] The design and functionality of such load-absorbing devices have been fully described above. This design and functionality also apply to vehicle occupant protection systems that use such devices. Therefore, to avoid unnecessary repetition, please refer to the section above discussing this device.
[0035] According to another aspect, the present invention relates to a method for operating a vehicle occupant protection system in a vehicle, wherein the vehicle includes: a seat for accommodating occupants, wherein the seat is slidably connected to the vehicle via a load-absorbing device according to any one of claims 1 to 8, and wherein a locking arrangement is provided, the locking arrangement being configured to selectively lock the vehicle seat in a defined seating position to prevent mutual displacement between the rails in the rail arrangement when locked, and to allow displacement between the rails in the rail arrangement when unlocked. The method includes:
[0036] By using collision sensor elements, we can determine whether a vehicle collision is imminent or ongoing.
[0037] The seating position is determined by using a seating position sensor element;
[0038] When it is determined that the seat is in a rear-facing position and a vehicle collision is imminent or ongoing:
[0039] The locking arrangement is unlocked to allow the seat to slide from the rear-facing position toward the regular driving position, and the inertial energy from the vehicle collision is used to slide the seat from the rear-facing position toward the regular driving position, while the inertial energy of the seat and / or the seated occupant is absorbed by the deformation of the strip in the load-absorbing device.
[0040] The design and functionality of such load-absorbing devices have been fully described above. This design and functionality also apply to the methods of operating occupant protection systems in vehicles using such devices. Therefore, to avoid unnecessary repetition, please refer to the section above discussing this device.
[0041] Other objects and advantages of the present invention will be apparent to those skilled in the art from the following detailed description of different embodiments. Attached Figure Description
[0042] The present invention will be described in detail with reference to the schematic diagram.
[0043] Figure 1 A component has been disclosed as part of an energy absorption device for use with vehicle seats.
[0044] Figure 2 An implementation plan for the strip was made public.
[0045] Figure 3 An energy absorption device under assembly conditions has been disclosed.
[0046] Figure 4 The energy absorption device integrated with the vehicle seat is shown in a highly schematic manner.
[0047] Figure 5A and Figure 5B The operation of the energy absorption device under conditions where it is activated but not yet displaced is schematically disclosed.
[0048] Figure 6A and Figure 6B The operation of the energy absorption device under conditions where energy absorption has already begun is schematically disclosed.
[0049] Figure 7A and Figure 7B The operation of the energy absorption device after energy absorption is completed is schematically disclosed.
[0050] Figure 8A and Figure 8B The absorption force is schematically disclosed as a function of the mutual displacement between the upper and lower guide rails, thereby deforming the strip.
[0051] Figure 9The method of operating a system using such a device is illustrated schematically. Detailed Implementation
[0052] Now go to Figure 1 The overall design of the load-absorbing device 100 for use with a vehicle seat is shown in an exploded view. The device 100 includes a guide rail arrangement in the form of an upper guide rail 1, a lower guide rail 2, a strip 3, and a locking arrangement 4 configured to selectively interlock the upper guide rail 1 and the lower guide rail 2. The upper guide rail 1 is configured to be slidably received in and along the lower guide rail 2.
[0053] The upper guide rail 1 includes a U-shaped cross-sectional profile, wherein two opposing vertical sidewalls 5A and 5B merge with a central bottom wall 6. One of the sidewalls 5B merges with a strip support flange 7, which extends substantially parallel to the bottom wall 6 and outwards away from the U-shaped cross-sectional profile. The bottom wall 6 includes a pattern of through holes 8, thereby allowing the upper guide rail 1 to be securely mounted to the guide rail of the seat frame.
[0054] The width of the strip support flange 7 is slightly smaller than the width of the wider flange of the lower guide rail 2, which will be described below. The strip support flange 7 includes a through hole 8 in a first end of the strip support flange. The hole 8 is configured to lockably engage the locking arrangement 4 in a manner described below. The strip support flange 7 includes a recess 9 having a through hole 9 in a second end of the strip support flange. When the strip 3 is mounted between the upper guide rail 1 and the lower guide rail 2, the recess 9 provides support for one end of the strip 3. The upper guide rail 1 is preferably formed of a pressed metal sheet.
[0055] The lower guide rail 2 includes a C-shaped profile having a flat bottom wall 10 and two L-shaped sidewalls 11 extending from the bottom wall 10. The two L-shaped sidewalls 11 thereby form corresponding flanges 12A, 12B extending parallel to the bottom wall 10. One of the two flanges 12A, 12B is disclosed to be wider than the other flange. Those skilled in the art will recognize that the flanges may have the same width. One of the flanges, in the disclosed embodiment, is the wider flange 12A, and includes a through opening 13 at its first end, the through opening having a neck portion extending away from the bottom wall 10. The through opening 13 is configured to support the locking arrangement 4 in a manner described below.
[0056] The bottom wall 10 of the lower guide rail 2 includes a through opening 14 located below the wider flange 12A. This opening 14 is configured to allow for the secure mounting of one end of the strip 3. This will be described further below. The lower guide rail 2 is preferably formed of a pressed metal sheet.
[0057] Now go to Figure 2The strip 3 is formed as a longitudinally extending body. The strip 3 is formed of a metal plate. The strip 3 has a first leg 15A, a second leg 15B, and a curved portion 15C located between and connected to the first leg 15A and the second leg 15B. The curved portion 15C has a curvature of approximately 180 degrees, thereby giving the first leg 15A and the second leg 15B substantially parallel extensions. The free end of the first leg 15A forms the first end 16A of the strip 3. The free end of the second leg 15B forms the second end 16B of the strip 3. The first end 16A and the second end 16B of the strip 3 have corresponding through openings 17A and 17B, thereby allowing the strip 3 to be fixedly connected to the upper guide rail 1 and the lower guide rail 2, respectively.
[0058] Figure 1 The normal design of the strip 3 is disclosed, i.e., in its normal operation. The first leg 15A is substantially shorter than the second leg 15B. Furthermore, the second end 16B of the strip 3 is disclosed to be curved, such that it extends substantially in the same plane as the first leg 15A.
[0059] The second leg 15B has a first portion 18 starting from the second end 16B, which, as seen along the longitudinal extension of the strip 3, has a constant width and a constant cross-sectional area. The first portion 18 merges with a tapered portion 19, which tapers in the direction toward the curved portion 15C of the strip 3. Therefore, as seen in normal operation of the load-absorbing device 100, the tapered portion 19 is arranged adjacent to the curved portion 15C. In the context of this invention, normal operating conditions should be understood as conditions under which the load-absorbing device 100 is not subjected to impact.
[0060] The tapered portion 19 is disclosed as having a second tapered portion 19B and a first tapered portion 19A adjacent to the curved portion 15C. The first tapered portion has a first tapering angle α1 relative to the longitudinal centerline of the strip 3, and the second tapered portion has a second tapering angle α2 relative to the longitudinal centerline. The second tapering angle α2 is greater than the first tapering angle α1. As a non-limiting example, the first tapering angle α1 may be in the range of 1-10 degrees, while the second tapering angle α2 may be in the range of 10-30 degrees. Those skilled in the art will recognize that the tapered portion may have a consistent angle along its entire length. Regardless of the angle, the cross-sectional area of the strip gradually increases along the tapered portion 19.
[0061] The tapered portion 19 is disclosed as having the same tapering degree along the two opposing longitudinally extending edge portions of the strip 3. Therefore, the strip 3 is symmetrical along the longitudinal centerline of the strip 3.
[0062] The tapered portions 19, 19A, and 19B are disclosed as having straight longitudinal extensions. Those skilled in the art will recognize that other geometries, such as a single curved longitudinal extension, can be used. As seen relative to the longitudinal centerline of strip 3, the single curved extension is preferably concave. In yet another embodiment, the strip may have a stepped construction, with a gradually increasing cross-sectional area along its longitudinal extension.
[0063] Now go back to Figure 1 The strip 3 is configured to be fixedly connected to the upper guide rail 1 and the lower guide rail 2 via a first end 16A and a second end 16B. As seen in normal operation of the load-absorbing device, the first end 16A of the strip 3 closest to the bend 15C is configured to be fixedly connected to the bottom wall 10 of the lower guide rail 2. This is done by an undisclosed fixing member (such as a screw or rivet) extending through an opening 14 in the bottom wall 10 of the lower guide rail 2 and a through opening 17A in the first end 16A of the strip 3.
[0064] The second end 16B of the strip 3 is configured to be fixedly mounted to the second end of the upper guide rail 1, and more precisely, to the strip support flange 7. The strip 3 is oriented such that the curved portion of the strip 3 is arranged on the downwardly projecting wall portion of the recess 9. The strip 3 is fixed to the upper guide rail 2 by an undisclosed fixing member (such as a screw or rivet) extending through the opening 20 in the strip support flange 7 of the upper guide rail 1 and the through opening 17B in the second end 16B of the strip 3. The position of the strip 3 during installation can be, for example, in... Figure 5B I saw it in the middle.
[0065] Now go to Figure 3 The present disclosure discloses one embodiment of the load-absorbing device 100 under normal conditions prior to installation into a vehicle. As can be seen from this disclosure, the strip 3 will be received in the gap 21 between the downwardly projecting wall portion of the strip support flange 7 of the upper guide rail 1 and the bottom wall 10 of the lower guide rail 2. The strip 3 will be concealed.
[0066] The locking arrangement 4 protrudes away from the flange of the lower guide rail 2. See also Figure 1 Combination Figure 3 The locking arrangement 4 includes an unlocking element 22 and a locking pin 23. The unlocking element 22 can be an electromechanical, electromagnetic, or pyrotechnic unlocking element. The unlocking element 22 is connected to the locking pin 23. The locking arrangement 4 is mounted to the guide rails 1 and 2 such that the locking pin 23 engages the upper guide rail 1 and the lower guide rail 2 by extending through corresponding openings 8 and 13 in the two guide rails 1 and 2. The locking pin 23 thus prevents displacement between the upper guide rail 1 and the lower guide rail 2. When the unlocking element 22 is activated, the locking pin 23 retracts from the openings 8 and 13. This will be discussed further below.
[0067] As in Figure 3 As best seen, locking arrangement 4 includes connection interface 24 to allow locking arrangement 4 to be connected to the vehicle's ECU (Electrical Control Unit).
[0068] Now go to Figure 4 This diagram schematically illustrates the connection between the seat frame 200 and the load-absorbing device 100. The load-absorbing device 100 is configured to connect to the lower portion of the seat frame 200 via an upper guide rail 1. The lower guide rail 2 is then configured to connect to the vehicle floor. The lower guide rail is fixedly mounted. For ease of understanding, the floor and therefore the fasteners are omitted. The connection between the lower guide rail 2 and the floor can be made using any suitable, undisclosed fastening device (such as bolts).
[0069] Now go to Figure 5A and Figure 5B The operation of the load absorption device will be discussed. Figure 5A A perspective view of the load absorption device 100 is disclosed, in which the strip 3 is shown as a separate unit to better illustrate its shape. Figure 5B It is the cross-section of the load-absorbing device 100 along its longitudinal extension at the moment exactly after the deployment of the locking arrangement 4 but before the guide rails 1 and 2 shift relative to each other. For example, in Figure 5B As can be seen from the best view, the deployment of locking arrangement 4 has caused locking pin 23 to release its engagement with the through holes in the upper guide rail 1 and the lower guide rail 2. This allows the two guide rails 1 and 2 to shift relative to each other.
[0070] Figure 5B How the strip 3 is mounted between the guide rails 1 and 2 is clearly disclosed. The second end 16B of the strip 3 is fixedly mounted to the second end of the upper guide rail 1, and more precisely, to the strip support flange 7. The strip 3 is oriented such that the curved portion of the strip 3 is arranged on the downwardly projecting wall portion of the recess 9. The strip 3 is fixed to the upper guide rail 1 by an undisclosed fixing member (such as a screw or rivet) extending through the opening 20 in the strip support flange 7 of the upper guide rail 1 and the through opening 17B in the second end 16B of the strip 3. Correspondingly, the first end 16A of the strip 3 is fixed to the bottom wall 10 of the lower guide rail 2 by an undisclosed fixing member extending through the through opening 14. Alternatively, the strip 3 may be welded to the guide rails 1 and 2.
[0071] Now go to Figure 6A and Figure 6B The two guide rails 1 and 2 have been displaced relative to each other, so that the upper guide rail 1 has been displaced by a distance roughly corresponding to half the length of the lower guide rail 2. For example, in... Figure 6BAs best viewed, this is a cross-section of the device 100 along its longitudinal extension. Since the lower guide rail is fixed to the vehicle floor (not shown), the first end of the strip 3 connected to the lower guide rail 2 is stationary. The second end 16B of the strip 3, fixed to the upper guide rail 1 which shifts due to the forward movement of the seat (not shown), moves together with the upper guide rail 1. This mutual displacement between the guide rails 1 and 2 causes the curved portion 15C of the strip 3 to translate in the same direction as the upper guide rail 1, see the arrow. The convex portion 25 of the curved portion 15C thus forms a leading edge during the mutual displacement between the upper guide rail 1 and the lower guide rail 2.
[0072] Additionally, as in Figure 6A As can be seen from the best viewpoint, the relative lengths of the first leg 15A and the second leg 15B of strip 3 have been altered. The first leg 15A has become longer, while the second leg 15B has become shorter. This ratio is due to the translation of the curved portion 15C.
[0073] Now go to Figure 7A and Figure 7B The two guide rails 1 and 2 have been displaced relative to each other to such an extent that the inertial force has been completely absorbed by the strip 3. The upper guide rail 1 and the lower guide rail 2 have been displaced more or less by the full usable length of the strip 3. The curved portion 15C of the strip 3 has been forcibly translated to such an extent that the first leg 15A and the second leg 15B of the strip 3 have more or less the same length. Those skilled in the art recognize that the degree of translation of the curved portion 15C depends on the specific collision conditions and the progression of the increase in cross-sectional area as seen along the tapering portion of the strip 3. This will be discussed further below.
[0074] Now go to Figure 8A and Figure 8B . Figure 8A An example of a strip 3 having two consecutive tapered portions is disclosed. The first tapered portion 19A has a first tapering angle α1 relative to the longitudinal centerline of the strip 3. The second tapering portion 19B has a second tapering angle α2 relative to the longitudinal centerline of the strip 3. The second tapering angle α2 is greater than the first tapering angle α1. As seen under normal operating conditions of the strip 3, the first tapering portion 19A is arranged adjacent to the curved portion 15C. Figure 8BThis is a graph showing the force absorbed by the displacement between the upper and lower guide rails, and thus the translational distance of the curved portion 15C during such displacement. Point A in the graph indicates the displacement between the guide rails, where the curved portion 15C has been translated to such an extent that it reaches the position where the first tapered portion 19A merges with the second tapered portion B. Similarly, point B in the graph indicates the displacement between the guide rails, where the curved portion 15C has been translated to such an extent that it reaches the position where the second tapered portion 19B merges with the portion 19C of the strip 3 having a consistent width. As can be seen from the graph, the geometry of the strip, having a gradually increasing cross-sectional area as seen along the longitudinal extension of the strip, allows for gradual absorption of the load, and thus, gradual absorption of energy from impacts.
[0075] Although the graph illustrates the performance of a strip with two tapered sections combined with a straight section of uniform width and therefore uniform cross-sectional area, the same principle applies to other strip geometries, i.e., strips with other geometries as seen along their longitudinal extension. The wider the strip and therefore the larger its cross-sectional area, the more energy is required to deform it, and therefore the higher the load absorption.
[0076] Now go back to Figure 4 The actual operation of the load-absorbing device 100, which is part of a vehicle occupant protection system 1000, will be described. The system 1000 includes a vehicle seat 300 configured to accommodate an occupant (details omitted). The occupant can set the backrest tilt and also move the seat forward and backward to a comfortable position. A seat frame 200 is connected to two load-absorbing devices 100 of the type described above. The devices 100 are secured to the base plate, for example, by bolts.
[0077] Each load-absorbing device 100 includes a locking arrangement 4 configured to selectively lock the vehicle seat in a defined seating position to prevent displacement between the guide rails 1 and 2 in the load-absorbing device 100 when locked, and to allow displacement between the guide rails 1 and 2 when unlocked. By default, the locking arrangement 4 is preferably set to the locked position during normal operation of the vehicle. This prevents displacement between the guide rails 1 and 2 during normal operation of the vehicle.
[0078] System 1000 includes at least one collision sensor element 400 adapted to determine an impending or ongoing vehicle collision. The system also includes a seating position sensor element 500 adapted to determine a seating position. Sensor 500 may, for example, determine the tilt of the backrest and the position of the seat relative to the dashboard or steering wheel. These types of sensors are well known in the art and will not be discussed further.
[0079] Sensors 400 and 500 and locking arrangement 4 are then arranged to communicate with the vehicle's ECU (Electrical Control Unit). When the ECU's processor determines, based on signals from collision sensor element 400, that an impending or ongoing vehicle collision exists and seating position sensor element 500 indicates that the seating is set in a specific position where there is a risk of skidding, the ECU will instruct locking arrangement 4 to unlock. This will allow upper guide rail 1 and lower guide rail 2 to shift relative to each other, thereby allowing load absorption by strip 3. Another parameter that can be used as an input to the ECU to determine whether locking arrangement 4 should be unlocked is the vehicle's speed. If the speed is below a certain threshold, the load from the collision will then be handled by other safety systems in the vehicle.
[0080] Upon impact, the inertial forces from the collision and the seated occupant will force seat 300 to slide forward from a rear-facing position toward a conventional driving position. This sliding is permitted by the mutual displacement between the upper guide rail 1 and the lower guide rail 2. Since the two guide rails are interconnected by a strip 3, the strip 3 is forcibly deformed, thereby absorbing the inertial energy of the seat and / or the seated occupant.
[0081] In short, see Figure 9 The method of operating the vehicle occupant protection system can be summarized as follows: determine the vehicle collision that is about to occur or is occurring by using the collision sensor element 400;
[0082] The seating position at 1200 is determined by using the seating position sensor element 500;
[0083] When it is determined that seat 200 is in a rear-facing position and a vehicle collision is imminent or ongoing:
[0084] Unlocking 1300 lock arrangement 4 to allow seat 200 to slide from rear-facing position toward regular driving position, and using 1400 inertial energy from vehicle collision to slide seat from rear-facing position toward regular driving position, while the inertial energy of seat and / or seated occupant is absorbed by deformation of strip 3 in corresponding load absorption device 100.
[0085] Therefore, a load-absorbing device is provided in which energy is absorbed by deforming a strip arranged in a finite gap between two parallel guide rails. In the event of a collision that causes the occupant to move in the forward direction, the guide rails are displaced relative to each other due to the inertial energy of the seat and / or the seated occupant. The strip is oriented between the two guide rails such that the curved portion is configured to translate along the strip in the same direction as the upper guide rail during the mutual displacement between the upper and lower guide rails. This means that the two fixed ends of the strip will be forced toward each other by linear translation. During this translation, the relative lengths of the first and second legs will change, i.e., one leg will be shorter and the other longer. However, the strip in this manner does not substantially elongate. In addition, the radius in the curved portion will remain substantially the same throughout the translation. This allows for effective absorption of inertial energy from the seat and the seated occupant during a collision. When used in a vehicle seat, there will be a reduced risk of skidding and additionally reduced forces on the spine and pelvic region.
[0086] During the vehicle design phase, the characteristics of the strips can be adapted based on parameters such as vehicle type, seat type, expected seating position during normal use, and expected weight of average seat occupants. Non-limiting examples of adaptable strip characteristics include the type of material in the strip, such as tensile strength and the cross-sectional area of the strip as seen transversely to its longitudinal extension. Therefore, all seats in one and the same vehicle can be equipped with load-absorbing devices, but each device can be fitted with different strip designs.
[0087] Strip 3 has been disclosed as a strip with a tapered shape having two tapered portions arranged one after the other and merging with a portion having a constant width and therefore a constant cross-sectional area. Additionally, the tapered portions have been described as having straight edge portions. Those skilled in the art will recognize that the same effect of gradually increasing cross-sectional area along the longitudinal extension of the strip can be achieved using other geometries. As seen along the longitudinal extension of the strip, the edge portion may, for example, have a single curved extension. Alternatively, the edge portion may have a stepped geometry. Furthermore, only one tapered portion, or three or more tapered portions, may be applicable. Additionally, the tapering angle can be varied.
[0088] Those skilled in the art will recognize that features from the various embodiments disclosed herein can be combined with each other to provide other alternative embodiments.
Claims
1. A load-absorbing device for use with a vehicle seat, said device include: The guide rail arrangement includes an upper guide rail (1) and a lower guide rail (2), the upper guide rail being configured to connect to the lower side of the vehicle seat, and the lower guide rail being configured to be fixedly connected to the top surface of the vehicle floor. The upper guide rail (1) and the lower guide rail (2) are slidably connected to each other to allow longitudinal displacement between the upper guide rail (1) and the lower guide rail (2); and A strip (3) having: a first leg (15A) having a first end (16A), a second leg (15B) having a second end (16B), and a curved portion (15C) between the first leg and the second leg, wherein the first end (16A) is fixedly connected to the lower guide rail (2), and the second end (16B) is fixedly connected to the upper guide rail (1); wherein The curved portion (15C) is configured to translate in the same direction as the upper guide rail (1) during the mutual displacement between the upper guide rail (1) and the lower guide rail (2).
2. The load-absorbing device according to claim 1, wherein the convex portion (25) of the curved portion (15C) forms a leading edge during the mutual displacement between the upper guide rail (1) and the lower guide rail (2).
3. The load-absorbing device according to claim 1, wherein the first leg (15A) or the second leg along (15B) its longitudinal extension includes a tapered portion (19) that tapers in the direction toward the curved portion (15C).
4. The load-absorbing device according to claim 3, wherein, as seen in normal operation of the load-absorbing device, the tapered portion (19) is arranged adjacent to the curved portion.
5. The load absorption device according to claim 3, wherein the tapered portion (19) has the same tapering degree along the two opposing longitudinally extending edge portions of the strip (3).
6. The load absorption device according to claim 3, wherein the tapered portion (19) has a gradually increasing cross-sectional area.
7. The load absorption device according to claim 2, wherein the tapered portion (19) has a first tapered portion (19A) and a second tapered portion (19B), the first tapered portion having a first tapered angle α1 relative to the longitudinal center line of the strip (3), and the second tapered portion having a second tapered angle α2 relative to the longitudinal center line of the strip (3), wherein the second tapered angle is greater than the first tapered angle.
8. The load absorption device according to any one of the preceding claims, The load absorption device further includes a locking arrangement (4) that selectively interlocks the upper guide rail (1) and the lower guide rail (2).
9. A vehicle occupant protection system, the vehicle occupant protection system comprising: Vehicle seat (200), the vehicle seat being configured to accommodate occupants; The load-absorbing device (100) according to any one of claims 1 to 8, wherein the guide rail arrangement is configured to connect the vehicle seat to the vehicle floor; Locking arrangement (4), the locking arrangement being configured to selectively lock the vehicle seat in a defined seating position to prevent mutual displacement between the rails (1, 2) in the rail arrangement when locked, and to allow displacement between the rails in the rail arrangement when unlocked; A collision sensor element (400) adapted to determine an impending or ongoing vehicle collision; and Seating position sensor element (500), said seating position sensor element being adapted to determine a seating position; When it is determined that the guide rails (1, 2) in the guide rail arrangement have shifted to the position where the seat is set in the rear-facing position and a vehicle collision is imminent or ongoing, the locking arrangement (4) is configured to be unlocked, thereby allowing mutual displacement between the guide rails (1, 2) and thereby allowing the seat to slide from the rear-facing position toward the normal driving position; and Thus, the sliding of the seat from the rearward seating position toward the conventional driving seating position is performed by using the inertial energy from the vehicle collision, while the strip (3) is forcibly deformed and thereby absorbs the inertial energy of the seat and / or the seated occupant.
10. A method for operating a vehicle occupant protection system in a vehicle, the vehicle comprising: Seats for accommodating occupants, wherein the seats are slidably connected to the vehicle via a load-absorbing device (100) according to any one of claims 1 to 8, and The method includes a locking arrangement (4) configured to selectively lock the vehicle seat in a defined seating position to prevent displacement between the rails (1, 2) in the rail arrangement when locked, and to allow displacement between the rails (1, 2) in the rail arrangement when unlocked; the method includes: A vehicle collision that is about to occur or is occurring is determined by using a collision sensor element (400); The seating position (1200) is determined by using the seating position sensor element (500); When it is determined that the seat is in a rear-facing position and a vehicle collision is imminent or ongoing: Unlock (1300) the locking arrangement (4) to allow the seat to slide from the rear-facing position toward the conventional driving position, and use (1400) the inertial energy from the vehicle collision to allow the seat to slide from the rear-facing position toward the conventional driving position, while the inertial energy of the seat and / or the seated occupant is absorbed by the deformation of the strip (3) in the load-absorbing device (100).