Test device and method for a floor-side seat anchorage

Abstract

Testing device (9) for a floor-side seat anchorage of a vehicle seat (1), which is installed on fixed seat rails (5) via fastenings distributed in the longitudinal direction of the rails and deformable under crash loads with a vehicle body (2), characterized in that the testing device (9) contains, as fastenings, pivot bearings (11) arranged translationally fixed between a base plate (10) and the seat rails (5), and at least one measuring sensor which detects a deformation of the seat rails (5) under predetermined seat loads.

Description

[0001] The invention relates to a testing device and a testing method for the floor-side seat anchorage of a vehicle seat, which is installed on the fixed seat rail via fastenings distributed in the longitudinal direction of the rail and deformable under crash load, according to the preamble of patent claims 1 and 9, respectively.

[0002] Vehicle bodies are increasingly being designed with lightweight construction in mind. This also affects the floor-side seat attachments to the supporting structure of the vehicle body. These attachments are no longer rigid but deform in the event of a crash under the effect of the loads emanating from the seat, so that the attachment elements of the seat itself, in particular the seat rails, are more heavily involved in load-bearing. This applies in particular to vehicle seats with a safety belt system that is at least partially integrated into the seat, as known, for example, from DE 39 31 696 A1, DE 196 44 377 A1, or DE 691 02 723 T2. In this case, the seats are anchored in the backrest area to the rear supporting structure in the roof or floor area of ​​the body by lockable tension struts or straps, thus relieving the seat rails of the impact forces.However, this requires additional construction and weight and obstructs access to the rear cabin. DE 202 10 946 U1 describes a test bench for simulating a vehicle side impact. DE 699 35 026 T2 describes a seat weight measuring device. DE 10 2007 029 783 A1 describes a device and method for testing a motor vehicle seat.

[0003] The object of the invention is to design a testing device and a testing method of the type mentioned above in such a way that a seat anchorage on the rail side alone on the vehicle structure can be reliably tested in a simple manner up to crash conditions and can thus be designed in an optimal way with regard to weight and load.

[0004] This object is achieved according to the invention by a testing device and a testing method having the features of patent claims 1 and 9, respectively. Particularly preferred embodiments of the invention are described in the subclaims.

[0005] According to the invention, the load strength of the deformable seat connection in the critical area of ​​the fixed seat rails is tested in a structurally and technically simple manner by simulating the attachment of the seat rails to the vehicle structure via pivot bearings mounted on a rigid base plate, simulating the seat rail connection to the vehicle structure. During the test procedure, the seat is subjected to a test force specified in terms of height and direction, depending on the crash, and the resulting deformation of the seat rails is measured. Subsequently, a crash-resistant and weight-optimized rail concept is developed, either step by step through repeated tests or based on strength calculations, taking safety margins into account.According to the invention, a problem-free, realistic seat rail test is thus made possible and thus a rail design is made possible that fully meets the requirement for an impact-resistant lightweight construction and is included in the energy absorption in the event of a crash.

[0006] In order to be able to adapt the seat anchorage in the test device even more sensitively to the actual installation conditions, the pivot bearings, in a particularly preferred embodiment, have a torsional stiffness that can be adjusted according to claim 2.

[0007] According to claim 3, the invention can also be used in particular for vehicle seats which contain a seat-integrated safety belt system and are loaded with test bodies, i.e. in the simplest case with test weights or dummies, during the test process and which require a correspondingly highly impact-resistant seat anchorage.

[0008] In order to ensure that even the most unfavourable installation conditions are taken into account during the test procedure (worst case test), it is recommended according to claim 4 to anchor the seat rails to the base plate using only two end-side pivot bearings and / or to subject the vehicle seat according to claim 5 to a predetermined test force in different seating positions with respect to the fixed seat rails.

[0009] According to claim 6, the sensors can be constructed in a particularly simple manner by means of angle sensors that indicate the rotational position changes of the pivot bearings. Alternatively, other sensors, such as electronic sensors, can also be used, which measure the rotational angle deflection of the pivot bearings or the deflection of the seat rails under load.

[0010] The test system according to the invention is equally suitable for a non-destructive, quasi-static test method, according to which the base plate is held stationary and the seat is subjected to a test force increasing up to a predetermined level by an external actuator, as is preferred according to claim 7, as well as alternatively according to claim 8 for a dynamic test method, in which the base plate together with the test specimen-loaded seat fastened to it via the pivot bearings is accelerated on a catapult sled up to a preselected speed and then decelerated under crash conditions.

[0011] The procedural aspect of the testing system according to the invention is characterized in claim 9.

[0012] The invention will now be explained in more detail using an exemplary embodiment in conjunction with the drawings. They show, in a highly schematic representation: Fig. 1 a partial side view of a motor vehicle in the area of ​​a vehicle seat provided with a seat-integrated belt system in the fully installed state; and Fig. 2 one of the Fig. 1 corresponding representation of a test device designed according to the invention.

[0013] In Fig. 1 shows a vehicle seat 1 installed on a vehicle body 2. In the event of a crash, the entire impact force is transmitted from the vehicle seat 1 via a deformable connection, designated overall by 3, to a support structure 4 of the vehicle body 2, illustrated by cross members 4.1, 4.2, i.e., successively via seat rails 5, on which the vehicle seat 1 is mounted in a positionally adjustable manner, the floor-side fastenings in the form of cross rails 6 connected at the ends to the seat rails 5, and from there via the vehicle floor 7 of the vehicle body 2 running between the support structure 4.

[0014] The individual connecting elements—seat rails 5, cross rails 6, and vehicle floor 7—must be designed to transmit the impact force in a fracture-proof manner while simultaneously maintaining a low dead weight. The particularly critical connecting elements in this regard are the seat rails 5, which are clamped to the cross rails 6 and the vehicle floor 7 not rigidly but rather in a way that allows them to bend under load.

[0015] In the Fig. In the embodiment shown in Fig. 1, the vehicle seat 1 is provided with a seat-integrated belt system 8, so that the impact not only of the vehicle seat 1 itself, but also of the vehicle occupant belted thereto must be transmitted via the seat connection 3 to the supporting structure 4.

[0016] The following in connection with Fig. However, the test device 9 described in section 2 can also be used equally for vehicle seats 1 with only partially integrated or seat-independent belt systems.

[0017] With the Fig. The test device 9 shown in Figure 2 allows the load strength of the seat anchorage in the area of ​​the seat rails 5 to be determined under crash conditions in a very simple manner, both structurally and in terms of testing technology. The main components of the test device 9 are a rigid base plate 10 and pivot bearings 11 fastened to the base plate and pivotable at least about an axis running perpendicular to the plane of the drawing, on which the seat is secured to the fastenings of the seat rails 5, i.e., to the fastenings of the cross rails 6 according to Fig. 1, is mounted.

[0018] If the pivot bearings 11 are freely rotatable, the bending resistance of the cross rails 6 and the vehicle floor 7 is assumed to be negligibly small (worst-case simulation); however, for a more differentiated seat rail test, the torsional stiffness of the pivot bearings 11 can be variably adjusted on the spring elements 12 assigned to them.

[0019] Additionally, mechanical angle sensors 13 are arranged on each of the pivot bearings 11, which indicate the changes in the rotational position of the pivot bearings 11 during the test process. Instead, other sensors, such as electronic sensors or strain gauges, can of course also be used to measure the deflection of the seat rails 5 during the test process.

[0020] With the test device 9 designed in this way, both stationary and dynamic seat rail tests can be carried out.

[0021] In a stationary seat rail test, test specimens 14 are belted to the vehicle seat 1, which are modeled on a belted vehicle occupant in terms of weight and mass distribution. During the test process, the base plate 10, together with the vehicle seat 1 pivotally mounted thereon and now loaded with test specimens, is held stationary. An external actuator (not shown) applies successively increasing test forces P to the individual centers of mass of test specimens 14 and vehicle seat 1 up to a standardized level and in different directions. The resulting bending deformation of the seat rails 5 is determined using the angle sensors 13.

[0022] From the test results, a rail concept can then be developed either on the basis of FE calculations for different rail materials or through repeated test procedures with seat rails 5 that differ in material and design, or through a combination of both, which, while including sufficient safety reserves, has a high level of impact safety and, at the same time, a low dead weight.

[0023] The Fig.The test fixture 9 shown in Figure 2 is equally suitable for a dynamic, realistic, but also more cost-intensive seat track test. In this case, instead of the test weights 14, a dummy can be strapped to the vehicle seat 1, and then the base plate 10, together with the pivot-mounted and dummy-loaded vehicle seat 1, can be attached to a catapult sled, which is accelerated to a standardized speed and then decelerated due to the crash. In this way, the seat track concept developed using the stationary test method can be tested under real crash conditions and refined if necessary.

[0024] Numerous modifications are possible within the scope of the invention. For example, the pivot bearings 11 can also be replaced with other, mechanically equivalent connecting elements between the seat rails 5 and the base plate 10. Furthermore, in the illustrated embodiment, the contact surface of the seat rails 5 is located above the pivot bearing axes. However, it can also be relocated to the axis plane of the pivot bearings 11. List of reference symbols 1 vehicle seat 2 vehicle body 3 deformable seat connection 4 Supporting structure 5 seat rails 6 cross rails 7 Vehicle floor 8 Belt system 9 Test device 10 Base plate 11 pivot bearings 12 spring elements 13 angle sensors 14 test specimens P test force

Claims

[1] Test device (9) for a floor-side seat anchorage of a vehicle seat (1), which is installed on fixed seat rails (5) with a vehicle body (2) via fastenings distributed in the longitudinal direction of the rails and deformable under crash load, characterized by that the testing device (9) contains, as fastenings, pivot bearings (11) arranged translationally fixed between a base plate (10) and the seat rails (5) and at least one measuring sensor which detects a deformation of the seat rails (5) under predetermined seat loads. [2] Test device (9) according to claim 1, characterized by that the pivot bearings (11) have an adjustable torsional stiffness and are mounted on a rigid base plate (10). [3] Test device (9) according to claim 1 or 2, characterized by that the vehicle seat (1) has a seat-integrated belt system (8) and can be loaded with test bodies (14) for a test procedure. [4] Test device (9) according to one of the preceding claims, characterized by that the seat rails (5) are each fastened to the base plate (10) via two end-side pivot bearings (11). [5] Test device (9) according to one of the preceding claims, characterized by that the vehicle seat (1) can be subjected to a test force (P) specified in direction and / or height in different seating positions with respect to the fixed seat rails (5). [6] Test device (9) according to one of the preceding claims, characterized by that angle sensors (13) indicating changes in the rotational position of the rotary bearings (11) are provided as measuring sensors. [7] Test device (9) according to one of the preceding claims, characterized by that the base plate (10) is fixedly mounted together with the vehicle seat (1) and the vehicle seat (1) can be subjected to a test force by an external activator. [8] Test device (9) according to one of claims 1 to 6, characterized by that the base plate (10) together with the pivot-mounted vehicle seat (1) is mounted on a catapult slide which is decelerated under crash conditions. [9] Test method (9) for a floor-side seat anchorage of a vehicle seat (1) which is installed on fixed seat rails (5) with a vehicle body (2) via fastenings distributed in the longitudinal direction of the rails and deformable under crash load, characterized by that the vehicle seat (1) is connected to a base plate (10) on the seat rails (5) via pivot bearings (11) and is subjected to a test force (P) predetermined in direction and / or height under crash conditions and the resulting deflection of the seat rails (5) is measured.

Images