Arrangement of a rear seat system on a floor structure of a passenger car

Abstract

The invention relates to an arrangement of a rear seat system (1) on a floor structure (2) of a passenger car, with a front cross element (6) on which respective front fastening points (16) for a seat frame (17) of the rear seat system (1) are arranged, and with a rear cross element (7) arranged behind the front cross element (7) in the vehicle longitudinal direction (4), on which respective rear fastening points (18) for the seat frame (17) of the rear seat system (1) are arranged, wherein the rear cross element (7) is designed as a tailor-welded blank component (19) which has at least two mutually different wall thicknesses (29, 32) and at least two mutually different material qualities (34, 37).

Description

The invention relates to an arrangement of a rear seat installation on a floor structure of a passenger vehicle according to the preamble of claim 1.Rear seat systems of this type and their arrangement on a floor structure in the passenger vehicle are already sufficiently known from the general prior art. In this case, rear seat installations with a foldable backrest can be used, which can be locked on the one hand by means of a locking device engaging at the lower region of the backrest. Such rear seat systems or their locking device can be referred to in particular as a low lock. Alternatively, rear seat systems with a foldable backrest can be used, which can be locked in the upper region of the backrest between this locking device engaging a motor vehicle body. This can be referred to in particular as a high lock. Consequently, the backrest can be fixed at least indirectly on the motor vehicle body shell.It is an object of the present invention to provide an arrangement of a rear seat system on a floor structure of a passenger car, so that a weight of the passenger car can be kept particularly low.This object is achieved according to the invention by an arrangement of a rear seat system on a floor structure of a passenger vehicle having the features of claim 1. Advantageous embodiments with advantageous refinements of the invention are the subject matter of the dependent patent claims.The invention relates to an arrangement of a rear seat installation on a floor structure of a passenger vehicle.In particular, the rear seat system is arranged in an interior of the passenger vehicle. The rear seat system is arranged in a rear sub-region of the interior space, which is related to a vehicle longitudinal direction of the passenger vehicle, wherein this rear sub-region can be referred to in particular as a rear. The rear seat system can therefore be understood to mean, in particular, a second row of seats. Thus, in the interior, in the vehicle longitudinal direction, a first row of seats is arranged, for example, in front of the second row of seats, which row of seats has at least one seat system or a plurality of seat systems. The front row of seats is arranged in the front sub-region of the interior space. The rear seat system preferably has a plurality of seats, which are each provided for seating a person.The floor structure is preferably part of a body, which can be referred to in particular as a body structure. The body is preferably designed as a self-supporting body.The floor structure has at least one front transverse element, which is designed in particular as a front transverse element on the body shell side. The front transverse element is arranged, for example, in the region of a heel plate, in the region of which a vehicle floor, which runs in a front region of the interior in the vehicle longitudinal direction, rises upwards in the vehicle vertical direction, for example, at the height of the rear seat system. On the front transverse element, respective front fastening points for a seat frame of the rear seat system are arranged in order to fix this in particular on the body shell side. In other words, the front transverse element has a plurality of front fastening points, via which or at which the seat frame of the rear seat system is to be held or held.The floor structure further comprises a rear cross member arranged behind the front cross member in the vehicle longitudinal direction. This means that the rear transverse element extends further to the rear in the vehicle longitudinal direction at least in regions, in particular predominantly or completely, than the front transverse element. On the rear transverse element, respective rear fastening points for the seat frame of the rear seat system, in particular different from the front fastening points, are arranged, in particular in order to fix these on the body shell side. In other words, the rear transverse element has a plurality of rear fastening points, by means of which or at which the seat frame of the rear seat system is to be held or held.In order to be able to keep a weight of the passenger car, in particular of the floor structure, particularly low, it is provided according to the invention that the rear transverse element is designed as a tail welded blank component. In other words, it is provided that the rear transverse element is produced or produced by means of a tail welded blank (TWB). The tailored welded blank component can be understood here in particular as a sheet metal component which can also be referred to as a tailored blank. The rear transverse element or the tail welded blank component has at least two wall thicknesses that differ from one another and at least two material qualities that differ from one another. This means that the rear transverse element or the tail welded blank component has at least one first wall thickness and at least one second wall thickness different from the first wall thickness, as well as at least one first material quality and at least one second material quality different from the first material quality. In other words, the rear transverse element has different wall thicknesses and different material qualities in different length regions. Thus, the rear transverse element can have a first wall thickness and a first material quality in a first of the length regions and the second wall thickness and the second material quality in a further length region, in particular different from the first length region. Again in other words, the rear transverse element is designed as a sheet metal component, to which the rear seat system is or is fastened, for example screwed, via the rear fastening points, wherein the sheet metal component is designed as a laser blank having different sheet thicknesses and sheet metal grades. In particular, the sheet metal component consists of the laser blank or the tail-welded blank component.The door welded blank component can be understood to mean sheet metal blanks that are welded individually to one another, in particular by means of the door welded blank method, wherein the welding is carried out, for example, as a butt joint by means of laser welding. The different wall thicknesses can be understood to mean, in particular, different material thicknesses. The different material grades can be understood to mean, in particular, different material grades, in particular different material configurations, and / or different types of material, for example different types of steel.The invention is based in particular on the following findings and considerations: The rear seat system, which is referred to in particular as a rear seat, can be mounted, in the embodiment referred to as a high-lock, on body structures, in particular on the front and the rear transverse element, for example by means of screws. This can be referred to in particular as a high-lock rear seat system. In the case of a high-lock fastening of the second row of seats (high-lock), body-fixed screw-on points and / or nuts with additional components can be realized. Alternatively or additionally, these can be reinforced by means of so-called bulkhead plates. As a result, it can be possible to distribute operating loads in load paths provided for this purpose in the body structure and to create the highest possible connection rigidity.In contrast, when using a so-called low-lock seat, i.e. when forming the rear seat system as a low-lock seat, more load or particularly much load can be introduced into the vehicle body by the rear seat system than when using the high-lock seat. Bench seat connection points in the vehicle body can experience higher loads. Because the rear transverse element is designed as a tailored blank component, the rear transverse element can be formed in one piece, i.e. remain as it were in one piece, despite the different wall thicknesses and the different material qualities. Due to the different wall thicknesses and / or the different material qualities, the rear transverse element can be reinforced locally, in particular only, where this is necessary. As a result, for example, no further reinforcing components, bulkhead, holders or the like are necessary. This can lead to a weight reduction of the passenger car, in particular of the floor structure. Furthermore, the manufacturing cost of the passenger vehicle can be kept particularly low. Thus, cost reduction can be achieved. In particular, the connection for the rear seat system designed as a low-lock seat can be realized via the rear transverse element designed as a tail welded blank component. Overall, it can be seen that the body structure is designed to accommodate the second row of seats.In a further embodiment, it is provided that the rear transverse element has the first wall thickness and the first material quality in the first longitudinal region in which at least one of the rear fastening points is arranged and in the second longitudinal region in which at least one of the rear fastening points, i.e. at least one other of the rear fastening points, is arranged. This means that the rear transverse element has the same wall thickness in the first and in the second longitudinal region, that is to say in particular the same or the same wall thickness value of the wall thickness, and that the rear transverse element has the same or the same material quality in the first and in the second longitudinal region. In other words, the wall thickness is the same in the first and in the second length region and the material quality is the same in the first and in the second length region. Thus, in particular, the wall thickness values of the wall thicknesses in the first and the second length range are the same. The fact that the material qualities are the same can be understood in particular to mean that the first and the second length region are formed from the same material, in particular with the same material specification or the same material quality. Thus, those longitudinal regions in which the rear fastening points are arranged can be dimensioned particularly strongly in the same way, whereby the rear seat system can be connected particularly securely to the floor structure. For example, the longitudinal regions are spaced apart from one another, in particular in the transverse direction of the vehicle.In a further embodiment, it is provided that the first and the second length range are formed from a respective dual-phase steel. In other words, the first length region is formed from a first material and the second length region is formed from a second material, wherein the first material is a dual-phase steel and the second material is a dual-phase steel. The material quality of the first and second length range can thus be the dual-phase steel, that is to say steel of dual-phase steel quality. Dual-phase steel can be understood in particular as steel whose structure has a ferritic (soft) matrix into which an at least predominantly martensitic (strength-enhancing) second phase, in particular island-shaped, is embedded at grain boundaries. A proportion of martensite is, for example, between 10 and 40 percent. Because the length regions are formed from the dual-phase steel, the rear transverse element can be formed in a particularly stable manner at the fastening points. As a result, a mechanical load-bearing capacity of the rear transverse element in the region of the fastening points can be particularly increased. The rear seat installation can thus be connected particularly securely to the floor structure.In a further embodiment, it is provided that the rear transverse element has at least one third longitudinal region extending, in particular in the vehicle transverse direction of the passenger vehicle, between the first and the second longitudinal region. In other words, the third longitudinal region is arranged between the first and the second longitudinal region, in particular in the vehicle transverse direction. This means that the first and the second length region are connected to one another via the third length region, for example at least indirectly or directly. In the third longitudinal region, the rear transverse element has a second wall thickness different from the first wall thickness and a second material quality different from the first material quality. This means that a material of the third length region has the second wall thickness and the second material quality. In other words, the third longitudinal region has a different wall thickness and a different material quality with respect to the first and the second longitudinal region. The fact that the second wall thickness is different from the first wall thickness can be understood in particular to mean that a respective wall thickness value of the respective wall thickness in the respective length region is different in the third length region than in the first and the second length region. The fact that the second material quality is different from the first material quality can be understood in particular to mean that the first and the second length region are formed from a different material, in particular with a different material specification or material quality, as is the third length region. Preferably, the second wall thickness is smaller than the first wall thickness. Thus, the rear transverse element can be formed particularly stably in the region of the fastening points, i.e. in the first and the second longitudinal region, and the wall thickness can be kept particularly low in the third longitudinal region, as a result of which the weight of the rear transverse element can be kept particularly low. For example, the third longitudinal region is free of fastening points for fastening the rear seat system. This means that the third longitudinal region preferably does not have a fastening point via which the seat frame of the rear seat system can be fastened or is fastened.In the region of the rear fastening points, i.e. in the region of a seat connection of the rear seat system, a greater or particularly high sheet thickness, for example of 2.2 mm, than the first wall thickness may be necessary than in other regions of the rear transverse element. This may be necessary, for example, so that a weld nut is not torn from the sheet metal during static belt tensioning and / or in the event of a crash, that is to say the weld nut can be fastened particularly stably. In order to be able to keep the weight of the passenger vehicle particularly low and / or to be able to keep the production cost, in particular production costs, of the passenger vehicle particularly low, it is thus possible to use a smaller sheet thickness, for example of 1.4 mm, in the form of the second wall thickness, in non-critical regions, for example in the form of the third longitudinal region.In a further embodiment, it is provided that the third length region is formed from a microalloyed steel. The microalloyed steel can be understood in particular as an unalloyed steel to which, for example, particularly small amounts of vanadium and / or niobium and / or titanium or the like are alloyed, in particular as a microalloying element. This embodiment is based in particular on the following findings and considerations:In order to be able to design the rear transverse element in a particularly stable manner in the region of the rear fastening points, that is to say in the region of a seat connection, it may be necessary to use at least one dual-phase steel for this purpose, that is to say in the first and the second length region. This can be shown, for example, by simulating a static belt pull and by a high-speed rear crash and / or a high-speed front crash. Due to complex component geometry, however, it may not be possible or may be particularly difficult to produce the complete rear transverse element in this quality, i.e. as dual-phase steel. In particular in areas with a particularly high degree of deformation, the microalloyed steel can therefore be used. Thus, the third length range is, for example, a length range with a high or particularly high degree of deformation. On the one hand, the weight of the passenger car can thus be kept particularly low and, on the other hand, the passenger car, in particular its floor structure, can be produced with particularly low outlay.In a further embodiment, it is provided that a respective edge region adjoins the first and the second longitudinal region in each case outwards in the vehicle transverse direction. In other words, the rear transverse element has at least two edge regions, wherein a first of the edge regions adjoins the first longitudinal region outwards in the vehicle transverse direction, in particular at least indirectly or directly, and the second edge region adjoins the second longitudinal region outwards in the vehicle transverse direction, in particular at least indirectly or directly. In other words, the first edge region is arranged further outwards in the vehicle transverse direction than the first length region and the second edge region is arranged further outwards in the vehicle transverse direction than the second length region. In the respective edge region, the rear transverse element has in each case a third wall thickness different from the first wall thickness and a third material quality different from the first material quality. In other words, the respective edge region has a different wall thickness and a different material quality with respect to the first and the second length region. The third wall thickness is preferably less than the first wall thickness. Thus, in an non-critical region of the rear transverse element in the form of the respective edge region, the corresponding wall thickness can be kept particularly low, as a result of which the weight of the passenger car or of the floor structure can be kept particularly low.Preferably, it is provided that the second wall thickness and the third wall thickness are the same. This means that the respective wall thickness value is equal to the respective wall thickness in the third length region and in the edge regions. Alternatively or additionally, the second material quality and the third material quality are the same. In other words, the third length region and the edge regions are formed from the same material, in particular with the same material specification or material quality. As a result, the production cost of the passenger vehicle can be kept particularly low.In a further embodiment, it is provided that the edge regions are formed from a microalloyed steel. It is thus possible, analogously to the third length range, to use steel with a lower quality for the edge region than in the first and the second length region. As a result, the rear transverse element can be produced with particularly low outlay, in particular when the rear transverse element has a particularly high degree of deformation in the edge regions.In a further embodiment, it is provided that the rear transverse element is held via the edge regions in each case on a respective body component of the floor structure, which body component is designed, for example, as a respective longitudinal member. In other words, the rear transverse element is connected, in particular directly, via the first edge region to a first body component, and the rear transverse element is connected, for example at least indirectly or directly, via the second edge region to a second body component, in particular formed separately from the first body component, of the floor structure. The respective body component is designed, for example, as a respective longitudinal member. As a result, the connection of the rear transverse element to the vehicle body components can be effected with particularly low outlay.In a further embodiment, it is provided that a backrest of the rear seat system can be folded about a pivot axis extending in a lower region and locked by means of a locking device engaging in the lower region of the backrest. The lower region can be understood here in particular as a lower region with respect to the vehicle vertical direction. Such a locking device (low lock) engaging in the lower region of the backrest has the particular advantage that no locking device has to be provided between the backrest and the body of the passenger car in the upper region of the backrest, but that the foldable backrest is fixed as a whole, for example, via respective seat fittings and, furthermore, via the seat frame. As a result, the rear seat system can be fastened particularly advantageously. In particular, no further fastenings are otherwise required for locking the foldable backrest. In addition, such a rear seat system with the locking device engaging in the lower region of the backrest can allow access to a receiving space in which, for example, components of an electrical energy store for electrically driving the passenger car, for example power electronics components, are arranged.Further features of the invention are evident from the claims, the figures and the description of the figures. The features and combinations of features mentioned above in the description and the features and combinations of features mentioned below in the description of the figures and / or shown alone in the figures can be used not only in the respectively specified combination but also in other combinations or alone.The invention will now be explained in more detail on the basis of a preferred exemplary embodiment and with reference to the drawings. The following are shown: FIG. 1 shows a schematic partial perspective view of an arrangement according to the invention of a rear seat system on a floor structure of a passenger vehicle; and FIG. 2 shows a schematic partial perspective view of the floor structure of the passenger vehicle of an arrangement according to the invention; and FIG. 3 shows a schematic perspective view of a rear cross element of an arrangement according to the invention.In the figures, identical or functionally identical elements are provided with identical reference symbols.FIG. 1 shows a schematic and perspective partial view of an arrangement of a rear seat system 1 of a floor structure 2 of a body of a passenger vehicle. This floor structure 2 can be seen in FIG. 2 in a schematic and perspective partial view with the rear seat installation 1 omitted. Thus, the rear seat system 1 is not shown in FIG. 2.A combination of FIGS. 1 and 2 reveals that the floor structure 2 in the exemplary embodiment comprises respective lateral longitudinal members 3 which extend in the vehicle longitudinal direction 4 from front wheel houses, which cannot be seen, to rear wheel houses 5. A front transverse element 6, in particular in the form of a cross member, extends between the lateral longitudinal members 3. The front transverse element 6 is designed in the exemplary embodiment as a heel element, in particular as a heel plate. A front vehicle floor is arranged on the front transverse element 6, for example, which extends forwards in the vehicle longitudinal direction 4, for example, as far as a lower end of a front end wall or a cross member arranged in this region. In particular, the front vehicle floor terminates at the front transverse element 6 toward the rear in the vehicle longitudinal direction 4. Above this front vehicle floor, for example, vehicle seats of a front row of vehicle seats are arranged. The rear seat system 1 is a rear vehicle seat row arranged behind the front seat row in the longitudinal direction 4 of the vehicle.Behind the front cross element 6 in the longitudinal direction 4 of the vehicle, a rear cross element 7 of the floor structure 2 is arranged. The rear transverse element 7 is, for example, part of a transverse structure 8, which is composed, for example, of a plurality of sheet metal components, wherein, for example, one of these sheet metal components is the rear transverse element 7. the rear transverse element 7 extends, for example, in relation to the vehicle longitudinal direction 4 at the front between the two longitudinal members 3 and, in relation to the vehicle longitudinal direction 4, at the rear between lateral longitudinal members 9 of a rear vehicle 10 of the vehicle body. The rear vehicle 10, in particular the lateral longitudinal members 9, adjoin rear ends of the lateral longitudinal members 3 to the rear, for example, in the longitudinal direction 4 of the vehicle. From the rear vehicle 10, a further cross member 12 extending behind the transverse element 7 thereof in the longitudinal direction 4 of the vehicle and in particular parallel thereto in the transverse direction 11 of the vehicle and a rear floor 13 can also be seen.In the exemplary embodiment, the front transverse element 6 and the rear transverse structure 8 delimit a receiving space 30, in which components of the energy store for electrically driving the passenger vehicle, for example power electronics components, are accommodated in the present case.A combination of FIGS. 1 and 2 also shows that in the exemplary embodiment the front transverse element 6 comprises respective support elements 15 which extend upward in the vehicle vertical direction 14 and at which respective fastening points 16 are provided for fastening a seat frame 17 of the rear seat system 1. In the present case, four support elements 15 and thus also four front fastening points 16 are provided for the rear seat system 1 or its seat frame 17.On the rear transverse element 7 there are arranged rear fastening points 18 which are provided for the seat frame 17 of the rear seat system 1. This means that the rear transverse element 7 comprises the rear fastening points 18 via which the seat frame 17 of the rear seat system 1 is to be held or held. The rear seat system 1 can be fixed on the top side via the fastening points 16, 18. In the exemplary embodiment, it is provided that the front and the rear cross elements 6, 7 are spaced apart from one another in the vehicle longitudinal direction 4. The rear fastening points 18 are illustrated in FIG. 3, in which the rear transverse element 7 is shown in a schematic perspective view. For example, the respective transverse element 6, 7 is screwed to the seat frame 17, in particular directly, at the respective fastening point 16, 18.In order to be able to keep a weight of the passenger car, in particular of the floor structure 2, particularly low and in particular to be able to keep a production outlay of the passenger car or of the floor structure 2 particularly low, it is provided that the rear transverse element 7 is designed as a tail welded blank component 19 which has at least two wall thicknesses 29, 31 or 29, 32 different from one another and at least two material grades 34, 36 or 34, 37 different from one another.In the exemplary embodiment, the rear transverse element 7 has at least three longitudinal regions 20, 21, 22. These longitudinal regions 20, 21, 22 can be understood to mean, in particular, longitudinal regions 20, 21, 22 extending in the vehicle transverse direction 11. Furthermore, in the exemplary embodiment, the rear transverse element 7 has two edge regions 23, 24, wherein the edge regions 23, 24 can be understood to mean, in particular, a fourth and a fifth longitudinal region of the rear transverse element 7. Furthermore, the edge regions 23, 24 can be understood to mean edge regions 23, 24 of the rear transverse element 7, in particular those relating to the vehicle transverse direction 11. In the exemplary embodiment, it is provided that the rear transverse element 7 is held via the edge regions 23, 24 in each case on a respective body component 3 aof the floor structure 2 in the form of the respective longitudinal member 3. In particular, the length regions 20, 21, 22 and the edge regions 23, 24 are formed by the tail welded blank component 19. In a first of the length regions 20, at least a first of the rear fastening points 18, for example exactly one rear fastening point 18, is arranged. In a second of the length regions 21, at least one other of the fastening points 18 is arranged, which can be referred to in particular as a second of the fastening points 18. In the exemplary embodiment, two of the rear fastening points 18 are arranged in the second longitudinal region 21, which can be referred to in particular as second and third fastening points 18. The third longitudinal region 22 extends between the first and the second longitudinal region 20, 21, The first and the third longitudinal region 20, 22 are connected to one another via a first transition region 25, in particular directly, which is designed, for example, as a laser weld. The second and the third longitudinal region 22, 23 are connected to one another via a second transition region 26, in particular directly, which is designed, for example, as a laser weld. The first longitudinal region 20 and a first of the edge regions 23 are connected to one another via a third transition region 27, in particular directly, which is designed, for example, as a laser weld. The second longitudinal region 21 and the second edge region 24 are connected to one another via a fourth transition region 28, in particular directly, which is designed, for example, as a laser weld. The respective laser weld seam can be referred to in particular as a laser seam. The rear transverse element 7 can therefore also be referred to as a laser printed circuit board.In the first longitudinal region 20 and in the second longitudinal region 21, the rear transverse element 7 has, for example, a first wall thickness 29, which is, for example, 2.2 millimeters. In the exemplary embodiment, the rear transverse element 7 has, in the third longitudinal region 22, a second wall thickness 31 which is different from the first wall thickness 29 and is in particular smaller than the first wall thickness 29 and is, for example, 1.4 mm. Furthermore, in the exemplary embodiment, the rear transverse element 7 has in each case a third wall thickness 32 in the respective edge region 23, 24, which third wall thickness is different from the first wall thickness 29 and is in particular smaller than the first wall thickness 29. The second wall thickness 32 is 1.4 mm, for example. Thus, it can be provided that the second wall thickness 31 and the third wall thickness 32 are the same. In other words, the edge regions 23, 24 each have the second wall thickness 31. However, it is of course alternatively possible for the second and the third wall thicknesses 31, 32 to be different from one another. Due to the different wall thicknesses 29, 31, 32, the rear transverse element 7 can be locally ideally adapted to mechanical loads acting on the rear transverse element 7, for example in the event of an accident. This can be achieved by local material savings in a particularly weight-saving manner.Furthermore, the rear transverse element 7 has a first material quality 34 in the first longitudinal region 20 and in the second longitudinal region 21 in the exemplary embodiment. In the third longitudinal region 22, the rear transverse element 7 has, for example, a second material quality 36 different from the first material quality 34. Furthermore, the rear transverse element 7 in the present case has in the respective edge region 23, 24 a third material quality 37 different from the first material quality 34. Preferably, the second and third material grades 36, 37 are the same. In other words, the edge regions 23, 24 have the second material grade 36. However, it can of course alternatively be provided that the second and the third material grade 36, 37 are different from one another.In the exemplary embodiment, it is furthermore provided that the first and the second length regions 20, 21 are formed from a dual-phase steel 39. Thus, the first material grade 34 is formed according to the dual-phase steel 39. Furthermore, in the exemplary embodiment, the third longitudinal region 22 and the edge regions 23, 24 are formed from a, in particular respective, microalloyed steel 40. Thus, the second material grade and the third material grade 36, 37 are formed according to the microalloyed steel 40. Thus, it is provided, for example, that the first, the second and the third length regions 20, 21, 22 are formed from steel, wherein the steel according to the first material grade 34 preferably has a greater yield strength than the steel according to the second material grade 36. Alternatively or additionally, the first and the second longitudinal region 20, 21 and the edge regions 23, 24 are formed, for example, from steel, wherein the steel according to the first material grade 34 preferably has a greater tensile strength, for example at least a tensile strength 1.5 times as great, than the steel according to the third material grade 37. In particular, the edge regions 23, 24 are formed from steel with the third material grade 37. In the present case, the tensile strength of the first material grade is, for example, at least 450 MPa and the tensile strength of the second material grade 36 and of the third material grade 37 is, for example, at least 780 MPa. For example, the first and second length regions 20, 21 are formed from the steel CR440Y780T. For example, the third longitudinal region 22 and / or the edge regions 23, 24 are formed from the steel CR380LA. In other words, the first material grade is, for example, 34 steel CR440Y780T and the second and third material grades 36, 37 are, for example, steel CR380LA.For example, it is provided that the edge regions 23, 24 have a higher degree of forming than the first and the second longitudinal region 20, 21, in particular the third longitudinal region 22, This means that, for producing the rear transverse element 7, in particular from a tailored blank, by means of forming, the edge regions 23, 24 are to be formed or are formed more extensively, that is to say more strongly, than the first and the second longitudinal region 20, 21 and in particular the third longitudinal region 22, This means in particular that, for producing the rear transverse element 7 during forming, more forming steps are to be carried out or are carried out than in the first and the second longitudinal region 20, 21 and in particular in the third longitudinal region 22, that is to say the outer edge regions 23, 24 can be a respective region 45 with a high or particularly high degree of forming. This can be made possible by the third material quality of the edge regions 23, 24, and in particular by using the steel CR380LA. As a result, the rear transverse element 7 can be produced in a particularly low-cost manner in a particularly weight-saving manner. The higher degree of deformation can be understood in particular to mean that a respective geometry, in particular surface geometry, of the respective edge region 23, 24 has more, in particular local, changes of direction and / or is designed to be more delicate than the first and the second longitudinal region 21, 22, and in particular the third longitudinal region 23.In the exemplary embodiment, it is provided that a backrest 41 of the rear seat system 1 can be folded about a pivot axis 43 running in a lower region 42 and can be locked by means of a locking device 44 engaging in the lower region 42 of the backrest 41. In other words, the locking of the backrest 41 or respective backrests 41 of the rear seat system 1 takes place, in particular exclusively, in the lower region 42. The backrest 41 can have a plurality of backrest parts which can each be assigned to a respective seat of the rear seat system 1. Folding the backrest 41 can be understood in particular to mean pivoting of the backrest 41, for example to at least one seat part 44 of the rear seat system 1, about the pivot axis 43.The described arrangement thus enables the use of the rear seat system 1 designed as a low-lock seat. A low-lock rear seat can therefore be installed, as a result of which a bracket for a rear seat backrest lock, in contrast to the high-lock seat, is no longer screwed to the body shell, for example. The backrest and the seat surface of the rear seat system 1 can be represented in a seat structure. By using the rear transverse element 7, which is in particular referred to as a laser printed circuit board and is designed as a tail welded blank component 19, weight savings and savings of production costs can be made possible. In this case, for example, a connection of the backrest 41, which is designated in particular as a rear seat backrest, in particular centrally, to a cross member arranged in the region of a luggage compartment floor can be avoided. This cross member can be referred to in particular as a „Q uerborn luggage compartment floor at the front". A reinforcement of a central bearing for the backrest 41 can likewise be omitted. Furthermore, a connection of the backrest 41, in particular in an outer region referred to the vehicle transverse direction 11, to an additional component provided for reinforcing an outer backrest bearing can be avoided. This backrest bearing can be referred to in particular as "backrest bearing on the outside". In addition, a connection of the backrest 41, in particular in an outer region related to the vehicle vertical direction 14, to an additional component provided for reinforcing an upper backrest bearing can be avoided. This backrest bearing can be referred to in particular as "backrest bearing at the top". It can be provided that a central automatic belt device, i.e. an automatic belt device provided for a central seat of the rear seat system 1, is integrated into the rear seat system 1. This can lead to additional introduction of force, as a result of which particularly high forces can be introduced into the vehicle body via a seat structure of the rear seat system 1 in the static belt tensioning and in the event of a rear crash or front crash, in particular a high-speed rear crash or high-speed front crash. The rear transverse element 7 designed as a tail welded blank component 19 nevertheless makes it possible to avoid additional parts, such as bulkhead, reinforcements or the like. As a result of the integrated automatic belt mechanism, the two fastening points 18, for example, are provided in the second longitudinal region 21. The fact that two of the fastening points 18 are arranged in the second longitudinal region 21 can therefore be particularly expedient for the central automatic seat mechanism, in particular a seat-integrated central automatic seat mechanism. Furthermore, particularly few screw points can be possible in the connection of the backrest 41 in the low-lock seat via weld nuts. This can result in a high acting force per screw point. In this case, the central seat can provide additional load. By means of the rear transverse element 7, in particular by means of its described configuration with regard to the wall thicknesses 29, 31, 32 and material grades 34, 36, 37, this load can be sustained.List of reference characters1 Rear seat system 2 Floor structure 3 Longitudinal member 3 a Karosserie component 4 Vehicle longitudinal direction 5 Wheel arch 6 Front transverse element 7 Rear transverse element 8 Transverse structure 9 Rear longitudinal member 10 Rear vehicle 11 Vehicle transverse direction 12 Further transverse member 13 Rear floor 14 Vehicle vertical direction 15 Support element 16 Front fastening points 17 Seat frame 18 Rear fastening points 19 Door welded blank component 20 First longitudinal region 21 Second longitudinal region 22 Third longitudinal region 23 First edge region 24 Second edge region 25 First transition region 26 Second transition region 27 Third transition region 28 Fourth transition region 29 First wall thickness 30 Receiving space 31 Second wall thickness 32 Third wall thickness 34 First material grade 36 Second material grade 37 Third material grade 39 Dual-phase steel 40 Microalloyed steel 41 Backrest 42 Lower region 43 Pivot axis 44 Seat part 45 Region

Claims

Arrangement of a rear seat system (1) on a floor structure (2) of a passenger vehicle, having a front transverse element (6) on which respective front fastening points (16) for a seat frame (17) of the rear seat system (1) are arranged, and having a rear transverse element (7) arranged behind the front transverse element (7) in the vehicle longitudinal direction (4), on which rear fastening points (18) for the seat frame (17) of the rear seat system (1) are arranged, characterized in thatthe rear transverse element (7) is designed as a tailor welded blank component (19), which has at least two wall thicknesses (29, 32) which differ from one another and at least two material grades (34, 37) which differ from one another.Arrangement according to Claim 1, characterized in that the rear transverse element (7) has a first wall thickness (29) and a first material quality (34) in a first longitudinal region (20) in which at least one of the rear fastening points (18) is arranged, and in a second longitudinal region (21) in which at least one of the rear fastening points (18) is arranged.Arrangement according to Claim 2, characterized in that the first and the second length region (20, 21) are formed from a dual-phase steel (39).Arrangement according to Claim 2 or 3, characterized in that the rear transverse element (7) has a third longitudinal region (22) which extends between the first and the second longitudinal region (20, 21) and in which the rear transverse element (7) has a second wall thickness (31) which is different from the first wall thickness (29) and is in particular smaller than the first wall thickness (29), and a second material quality (36) which is different from the first material quality (34).Arrangement according to Claim 4, characterized in that the third longitudinal region (31) is formed from a microalloyed steel (40).Arrangement according to one of Claims 2 to 5, characterized in that the first and the second longitudinal region (20, 21) are each adjoined outwards in the vehicle transverse direction (11) by a respective edge region (23, 24), in which the rear transverse element (7) has in each case a third wall thickness (32) which is different from the first wall thickness (29) and is in particular smaller than the first wall thickness (29), and a third material quality (37) which is different from the first material quality (34).Arrangement according to Claim 6 with reference back to Claim 4, characterized in that the second wall thickness (31) and the third wall thickness (32) are the same and / or the second material quality (36) and the third material quality (37) are the same.Arrangement according to Claim 6 or 7, characterized in that the edge regions (23, 24) are formed from a microalloyed steel (40).Arrangement according to one of Claims 6 to 8, characterized in that the rear transverse element (7) is held via the edge regions (23, 24) in each case on a respective body component (3a) of the floor structure (2).Arrangement according to one of the preceding claims, characterized in that a backrest (41) of the rear seat system (1) can be folded about a pivot axis (43) running in a lower region (42) and can be locked by means of a locking device engaging in the lower region of the backrest (41).

Images