DE102011080067B4 - Backrest of a motor vehicle seat - Google Patents

Abstract

Backrest of a motor vehicle seat with• a rigid, load-bearing backrest frame (1) made of• at least one upper cross member (13),• two side beams (11, 12)◯ with mutually facing, profiled inner contours and a spring mat (2) suspended in the backrest frame (1). ), which supports an upholstered body, wherein◯ the side rails (11, 12) are connected to a component (4, 5, 6; 10) which reinforces the buckling resistance of the side rails (11, 12), characterized in that the inner contours of the side rails ( 11, 12) are U- or L-shaped in cross section with a side part (30) aligned parallel to the longitudinal direction of the motor vehicle (X direction of the motor vehicle coordinate system) and at least one transverse part (31) angled from the side part (30) and that Component (4, 5, 6) extends at least partially diagonally to the side part (30) and the at least one transverse part (31) and is supported on supports of the side part (30) and / or the at least one transverse part (31).

Description

The invention relates to the backrest of a motor vehicle seat according to the preamble of claim 1.

From the DE 103 05 235 B3 a backrest of an upholstered vehicle seat is known, which has a backrest frame with at least one upper crossbar and two side bars, into which a spring mat supporting the upholstery is suspended. The cross beam or the cross member and the two side beams are usually made from a sheet steel and provided with a cross-sectional profile in order to meet the requirements for a lightweight vehicle seat with high rigidity, so that the motor vehicle seat can withstand the high loads that occur in the event of an accident despite being low in weight withstands and adequately supports the body of a vehicle occupant.

Despite the alignment of the flat side rails in the plane of a motor vehicle spanned by the the side rails can bend and thereby cause an increased risk of injury to the vehicle occupant.

In addition to the side rails bending in the event of a crash, there is also the risk that the side rails will turn away to the outside, so that the side parts of the side rails, which in the original state are parallel to one another, essentially in the X-Z plane of the motor vehicle coordinate system, run obliquely to one another. This results in a kink in the backrest frame of the backrest, so that people or objects behind the backrest are no longer supported by the backrest in the event of a crash and therefore endanger the vehicle occupant sitting on the motor vehicle seat.

This risk of the side rails turning away to the outside can be countered by using a greater sheet metal thickness for the side rails and/or by doubling the side rails, which, however, leads to increased vehicle weight, installation space and manufacturing effort as well as higher material and manufacturing costs.

From the DE 10 2009 025 780 A1 a U-shaped backrest frame for a vehicle seat with two vertical side rails and an upper cross rail connecting the side rails is known, in which the side rails and the cross rail consist of a half-shell made of metal and a half-shell sheet materially connected to the half-shell to increase stability. However, the increased stability of the backrest frame is associated with increased weight and increased manufacturing and material costs.

Additional backrests for a motor vehicle seat are in the documents DE 43 13 813 A1 , DE 10 2008 038 851 A1 , DE 10 2008 057 165 A1 , US 3,506,987 A , US 3,411,824 A , DE 10 2007 034 187 A1 , WO 98/32 357 A1 , US 4,192,545 A and WO 2004/016 462 A1 described.

The present invention is based on the task of increasing the buckling resistance of a backrest for motor vehicle seats with little material, manufacturing and assembly effort and with a minimal increase in the weight of the motor vehicle seat.

This task is solved according to the invention with the features of claim 1.

The solution according to the invention makes it possible to produce backrests for motor vehicle seats with high kink resistance without significantly increasing the material and manufacturing costs and thus the manufacturing costs and without significantly increasing the weight of the motor vehicle seat.

The solution according to the invention is based on the idea of increasing the buckling resistance of the side rails on the one hand by using the three-dimensional profile of the side rails by supporting the profile and on the other hand or additionally by holding the side rails in position even under high crash loads, i.e. H. their original shape with parallel alignment of the side parts of the side rails and their course in the Side rails and an increase in weight as well as increased material and manufacturing costs are required for the backrest frame.

Instead, in a first embodiment, a component with minimal weight that utilizes the three-dimensional profile of the side rails is inserted in a form-fitting manner into the profile of the side rails, with which the moment of resistance of the side rails and thus their buckling resistance is increased in the longitudinal direction or in the direction of the X-axis of the motor vehicle. This component can be made, for example, from a plastic or foamed metal material or in a preferred embodiment of the invention can be formed by modifying the spring mat suspended in the backrest frame.

In principle, in order to increase the buckling resistance of the side rails, a large-area component can be positively integrated into the inner contour of the side rails over essentially the entire length of the side rails in order to provide the side rails with increased kink resistance over their entire length. However, since the section of the side rails at risk of buckling is generally known or can be determined mathematically, through tests or empirically, instead of a large-area component, a component with a small area and low weight can be inserted into the section of the side rails at risk of buckling in the inner contour of the Side rails are used, which are supported on supports of the inner contour of the side rails, i.e. on the cross-sectional profile and / or catch beads of the side rails.

As a result of this design of the solution according to the invention, in addition to further weight savings, a reduction in the cost of materials and production costs is required because of the lower requirements for the accuracy of fit of the component to be inserted in a form-fitting manner into the side rail profile.

In order to provide high resistance to buckling in the event of a rear crash caused by the upper body of a motor vehicle occupant hitting the backrest, the side rails of the backrest frame extend essentially in the longitudinal direction, i.e. H. in the direction of the Accordingly, the component used as an anti-buckling element to increase the area moment of resistance extends in the longitudinal direction of the motor vehicle at least partially along the side part of the inner contour of the side rails and is supported on supports of the side part and / or on the at least one transverse part.

The component is arranged so that it extends at least partially diagonally to the side part and the at least one transverse part of the inner contour of the side rails and is supported on supports of the side part and/or on the at least one transverse part.

A preferred embodiment of the invention consists in forming the component from extended suspension wires of the spring mat into the side rails.

In this preferred embodiment, no separate components and separate assembly processes are required, since the existing suspension wires, in particular spring suspension wires, which are connected to the spring mat via a tension spring, are inserted in a form-fitting manner into the inner contour of the side rails with appropriate lengthening and shaping in such a way that an effective Support of the inner contour of the side rails and thus an increase in the axial moment of inertia results, so that a minimum moment of resistance of the backrest frame against buckling in the event of a rear crash is guaranteed.

Since using the extended suspension wires of the spring mat to increase the stability of the side rails against buckling in the event of a rear crash only results in a minimal increase in weight, but at the same time significantly increases the buckling resistance of the side rails and thus of the backrest frame, the side rails can have the same performance in terms of their buckling resistance as side rails , which provide the required buckling resistance by using stronger and therefore heavier material, are made from significantly thinner and therefore lighter material.

The positive arrangement and integration of the extended suspension wires into the inner contour of the side rails to increase the kink resistance of the side rails can be done with different shapes of the suspension wires and their positive insertion into the inner contour of the side rails using the various supports, with the suspension wires at least partially along the side part and / or guided diagonally to the side part and cross part of the inner contour of the side rails, supported on the supports and hung in an eyelet or opening in the side part of the side rails.

• - einen Verbindungsschenkel, der von der Federmatte zu einer durch den Eckbereich von Seitenteil und Querteil der Innenkontur des Seitenholms gebildeten Abstützung geführt ist,
• - eine sich am hinteren Querteil oder dem Eckbereich von Seitenteil und Querteil abstützende, durch Abwinklung gebildete Abstützkante,
• - einen sich entlang zumindest eines Teils des Seitenteils erstreckenden ersten Längsschenkel,
• - einen vom ersten Längsschenkel abgewinkelten Einhängehaken, der in die Öffnung oder Öse im Seitenteil des Seitenholms eingehängt ist und nach einer 180°-Abwinklung zurückgeführt ist,
• - einen parallel zum und dicht neben dem ersten Längsschenkel geführten zweiten Längsschenkel und
• - einen vom zweiten Längsschenkel abgewinkelten Endschenkel, der im Eckbereich von Seitenteil und Querteil abgestützt ist,

auf.In a first embodiment, the hanging wire is only slightly extended and pointed

• - a connecting leg which is guided from the spring mat to a support formed by the corner area of the side part and cross part of the inner contour of the side rail,
• - a support edge formed by an angle that is supported on the rear cross part or the corner area of the side part and cross part,
• - a first longitudinal leg extending along at least part of the side part,
• - a hanging hook angled from the first longitudinal leg, which is hooked into the opening or eyelet in the side part of the side rail and is returned after a 180 ° bend,
• - a second longitudinal leg guided parallel to and close to the first longitudinal leg and
• - an end leg angled from the second longitudinal leg, which is supported in the corner area of the side part and cross part,

on.

An additional increase in kink resistance can be achieved by arranging the first and second longitudinal legs of the suspension wires in a sleeve, so that in addition to doubling the longitudinal legs, their buckling resistance is further increased by combining the longitudinal legs in the sleeve.

• - einen Verbindungsschenkel, der von der Federmatte ausgehend abgewinkelt zu einer vom Seitenteil der Innenkontur entfernten Abkantung des hinteren Querteils geführt ist,
• - eine sich am hinteren Querteil oder dem Eckbereich von hinterem Querteil und Abkantung des hinteren Querteils abstützende, durch Abwinklung gebildete Abstützkante,
• - einen ersten Diagonalschenkel, der von der Abstützkante diagonal zur Öse oder Öffnung des Seitenteils geführt ist,
• - einen Einhängehaken, der in die Öse oder Öffnung des Seitenteils eingehängt ist,
• - einen Diagonal- oder Längsschenkel, der sich vom Einhängehaken entlang des Seitenteils oder schräg zum Seitenteil zu dem zwischen dem Seitenteil und dem hinteren Querteil gebildeten Eckbereich erstreckt und
• - einen vom Diagonal- oder Längsschenkel abgewinkelten Endschenkel, der im Eckbereich von Seitenteil und Querteil abgestützt ist,

aufweist.In a third embodiment, the resilience of the side rails against buckling is increased by the fact that the hanging wire is extended

• - a connecting leg which is guided at an angle from the spring mat to a fold of the rear cross part which is away from the side part of the inner contour,
• - a support edge formed by bending that is supported on the rear cross part or the corner area of the rear cross part and the fold of the rear cross part,
• - a first diagonal leg, which is guided diagonally from the support edge to the eyelet or opening of the side part,
• - a hanging hook that is hooked into the eyelet or opening of the side panel,
• - a diagonal or longitudinal leg which extends from the hanging hook along the side part or obliquely to the side part to the corner area formed between the side part and the rear cross part and
• - an end leg angled from the diagonal or longitudinal leg, which is supported in the corner area of the side part and cross part,

having.

For optimal adaptation to the inner contour of the side rail, the connecting leg preferably has a first section that is aligned essentially parallel to the spring mat and a second section that runs parallel to the fold of the rear cross part.

• - einen Verbindungsschenkel, der von der Federmatte ausgehend abgewinkelt zu einer vom Seitenteil der Innenkontur entfernten Abkantung des hinteren Querteils geführt ist,
• - eine sich am hinteren Querteil und der Abkantung des hinteren Querteils abstützende, durch Abwinklung gebildete Abstützkante,
• - einen ersten Diagonalschenkel, der von der Abkantung diagonal zu der Öse oder Öffnung des Seitenteils geführt ist,
• - einen Einhängehaken, der in die Öse oder Öffnung des Seitenteils eingehängt ist,
• - einen zweiten Diagonalschenkel, der parallel zum ersten Diagonalschenkel geführt ist und
• - einen vom zweiten Diagonalschenkel abgewinkelten Endschenkel, der im Eckbereich von Seitenteil und hinterem Querteil abgestützt ist,

auf, wobei auch in dieser Ausführungsform eine Doppelung der Diagonalschenkel zu einer Erhöhung der Knickbelastbarkeit der Seitenholme führt.In a fourth embodiment, the extended suspension wire

• - a connecting leg which is guided at an angle from the spring mat to a fold of the rear cross part which is away from the side part of the inner contour,
• - a support edge formed by an angle which is supported on the rear cross part and the fold of the rear cross part,
• - a first diagonal leg, which is guided diagonally from the fold to the eyelet or opening of the side part,
• - a hanging hook that is hooked into the eyelet or opening of the side panel,
• - a second diagonal leg, which is guided parallel to the first diagonal leg and
• - an end leg angled from the second diagonal leg, which is supported in the corner area of the side part and rear cross part,

on, whereby in this embodiment too, a doubling of the diagonal legs leads to an increase in the buckling resistance of the side rails.

In this embodiment, too, the buckling resistance can be further increased by arranging the diagonal legs in a sleeve that prevents the diagonal legs from buckling under high crash loads.

• - den Eckbereichen zwischen dem Seitenteil und dem mindestens einen, vorzugsweise hinteren Querteil und/oder
• - den Abkantungen oder Abkröpfungen des Seitenteils und/oder des mindestens einen Querteils und/oder
• - den Fangsicken des Seitenteils und/oder des mindestens einen Querteils

ausgebildet sind.What is essential in the form-fitting arrangement and integration of the extended suspension wires into the inner contour of the side rails is their support at the various possible support points, which are preferably and, if necessary, alternatively to the support points specified in the various embodiments

• - the corner areas between the side part and the at least one, preferably rear, cross part and/or
• - the folds or bends of the side part and/or the at least one cross part and/or
• - the catch beads of the side part and/or the at least one cross part

are trained.

One of the support points is formed by hooking the extended hanging wires into the side part of the inner contour of the side rails, with the hanging hook being formed from a back and forth guide of a hanging leg folded by 180 ° to stabilize the extended hanging wires.

Alternatively or in addition to a combination of double longitudinal or diagonal legs of the extended suspension wires, the extended suspension wires can be at least partially encapsulated with a plastic in the area running in the inner contour of the side rails, which not only leads to increased buckling resistance through the edging of the extended suspension wires, but also also contributes to increasing the buckling resistance through support at appropriate support points on the inner contour of the side rails.

In a second embodiment for increasing the buckling resistance of the backrest of a motor vehicle seat, a tension strut which essentially can be subjected to tensile force is provided which connects the side rails to one another.

The tension strut connecting the side rails keeps the side rails in position even under high crash loads, i.e. H. maintain their at least partially parallel alignment in the This averts the risk that people or things located behind the backrest could endanger the vehicle occupant sitting on the motor vehicle seat.

Compared to doubling the side rails or using a larger sheet metal thickness for the side rails or other reinforcing measures or additional components to ensure the required strength of the backrest frame even in the event of a crash, the integration of a tension strut achieves significant weight and cost savings and, if necessary, also enables retrofitting of a motor vehicle seat possible because, according to a further feature of the invention, the tension strut can be integrated into existing components of the backrest and their connection to the side rails, such as the spring mat.

Accordingly, the ends of the tension strut are connected to hooks or eyelets on the side rails, the tension strut is integrated into the spring mat and/or connected to the fastenings of the spring mat on the side rails.

Preferably, the tension strut consists of at least one steel cable, which requires minimal space and whose pretension can be varied to connect the side rails by simply changing the cable length.

The rope length change can preferably be carried out by means of a turnbuckle, which is integrated into the steel rope and moves the rope ends of the steel rope towards one another or away from one another by actuation.

The minimal effort associated with changing the cable length, which also has no effect on the other components that determine the buckling resistance of the backrest frame, further reduces the manufacturing and, in particular, the assembly costs.

Alternatively, the tension strut can consist of a steel sheet, which is provided in addition to the functional cross member and possible cross struts of the strength structure or the backrest frame of the backrest and is included in the manufacturing process of the strength structure.

• 1 eine schematisch-perspektivische Darstellung einer Rückenlehne eines Kraftfahrzeugsitzes mit einem Lehnenrahmen und einer in den Lehnenrahmen eingehängten Federmatte;
• 2 eine schematisch-perspektivische Darstellung von zur Außenseite der Rückenlehne weg gedrehten Seitenholmen des Lehnenrahmens nach einer dynamischen Crashbelastung;
• 3A - 3C schematische Darstellungen der Querschnittsveränderung eines Seitenholms des Lehnenrahmens bei einer dynamischen Crashbelastung;
• 4 eine schematisch-perspektivische Darstellung einer Rückenlehne mit einem formschlüssig in die Seitenholme integrierten großflächigen Bauelement zur Erhöhung der Knickbelastbarkeit der Seitenholme des Lehnenrahmens;
• 5 eine schematisch-perspektivische Darstellung eines Teils eines Seitenholms mit einem kleinen, formschlüssig in die Innenkontur des Seitenholms integrierten Bauelement an einer potentiellen Knickstelle zur Erhöhung der Knickbelastbarkeit des Seitenholms;
• 6A - 6C eine schematische Darstellung der Querschnittsveränderung eines Seitenholms mit integriertem Bauelement zur Erhöhung der Knickfestigkeit des Seitenholms;
• 7 eine Draufsicht auf einen Teil eines Seitenholms und eine Federmatte;
• 8 einen Schnitt entlang der Linie A - A gemäß 7 bei einer ersten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes mit parallel zum Seitenteil des Seitenholms geführten Längsschenkeln und einem Einhängehaken zum Einhängen des verlängerten Federmatten-Einhängedrahtes in eine Öffnung des Seitenteils des Seitenholms;
• 9 und 10 isometrische Ansichten eines Teils eines Seitenholms mit der ersten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes gemäß 8;
• 11 einen Schnitt entlang der Linie A - A gemäß 7 bei einer zweiten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes mit einem Diagonalschenkel, einem parallel zum Seitenteil des Seitenholms geführten Längsschenkel und einem Einhängehaken zum Einhängen des verlängerten Federmatten-Einhängedrahtes in eine Öffnung des Seitenteils des Seitenholms;
• 12 und 13 isometrische Ansichten eines Teils eines Seitenholms mit der zweiten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes gemäß 11;
• 14 einen Schnitt entlang der Linie A - A gemäß 7 bei einer dritten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes mit zwei parallelen Diagonalschenkeln und einem Einhängehaken zum Einhängen des verlängerten Federmatten-Einhängedrahtes in eine Öffnung des Seitenteils des Seitenholms;
• 15 und 16 isometrische Ansichten eines Teils eines Seitenholms mit der dritten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes gemäß 14;
• 17 eine schematische Querschnittsdarstellung durch einen Seitenholm einer Rückenlehne zur Erläuterung der bei einem Heckcrash auftretenden, auf den Seitenholm einwirkenden Crashkräfte;
• 18 eine schematische Querschnittsdarstellung des Seitenholms gemäß 17 mit darin eingetragener Hauptwirkungskontur des verlängerten Einhängedrahtes gemäß den 14 bis 16;
• 19 einen Schnitt entlang der Linie A - A gemäß 7 bei einer vierten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes mit zwei parallelen Diagonalschenkeln, einer die parallelen Diagonalschenkel umfassenden Hülle und einem Einhängehaken zum Einhängen des verlängerten Federmatten-Einhängedrahtes in eine Öffnung des Seitenteils des Seitenholms;
• 20 und 21 isometrische Ansichten eines Teils eines Seitenholms mit der vierten Ausführungsform eines verlängerten Federmatten-Einhängedrahtes gemäß 19;
• 22 eine schematisch-perspektivische Darstellung eines Lehnenrahmens und einer Einhängestelle in einen Seitenholm für die Federmatte;
• 23 eine schematisch-perspektivische Darstellung eines Teils des Seitenholms gemäß 22 mit in einer Schleife geführter Einhängedrahtverlängerung;
• 24 einen schematischen Querschnitt durch den Seitenholm gemäß 23 und der in einer Schleife nach unten geführten Einhängedrahtverlängerung;
• 25 eine schematisch-perspektivische Darstellung eines Lehnenrahmens mit einem in eine Querstrebe des Lehnenrahmens integrierten, die Seitenholme verbindenden Stahlseil und
• 26 eine schematisch-perspektivische Darstellung eines Lehnenrahmens mit einer Kombination aus einem in eine Querstrebe des Lehnenrahmens integrierten, die Seitenholme verbindenden Stahlseil und einer in die Seitenholme eingesetzten Einhängedrahtverlängerung für die Federmatte.

The essential features of the invention and its numerous possible variations will be explained using several exemplary embodiments shown in the drawing. Show it:

• 1 a schematic perspective view of a backrest of a motor vehicle seat with a backrest frame and a spring mat suspended in the backrest frame;
• 2 a schematic perspective view of the side rails of the backrest frame turned away from the outside of the backrest after a dynamic crash load;
• 3A - 3C schematic representations of the change in cross-section of a side rail of the backrest frame in the event of a dynamic crash load;
• 4 a schematic perspective representation of a backrest with a large component integrated positively into the side rails to increase the buckling resistance of the side rails of the backrest frame;
• 5 a schematic perspective representation of a part of a side rail with a small component, positively integrated into the inner contour of the side rail, at a potential kink point to increase the buckling load capacity of the side rail;
• 6A - 6C a schematic representation of the cross-sectional change of a side rail with an integrated component to increase the buckling resistance of the side rail;
• 7 a top view of part of a side rail and a spring mat;
• 8th a cut along the line A - A according to 7 in a first embodiment of an extended spring mat suspension wire with longitudinal legs guided parallel to the side part of the side rail and a suspension hook for hanging the extended spring mat suspension wire in an opening in the side part of the side rail;
• 9 and 10 Isometric views of part of a side rail with the first embodiment of an extended spring mat suspension wire according to 8th ;
• 11 a cut along the line A - A according to 7 in a second embodiment of an extended spring mat suspension wire with a diagonal leg, a longitudinal leg guided parallel to the side part of the side rail and a suspension hook for hanging the extended spring mat suspension wire in an opening in the side part of the side rail;
• 12 and 13 Isometric views of part of a side rail with the second embodiment of an extended spring mat suspension wire according to 11 ;
• 14 a cut along the line A - A according to 7 in a third embodiment of an extended spring mat hanging wire with two parallel diagonal legs and a hanging hook for hanging the extended spring mat hanging wire in an opening in the side part of the side rail;
• 15 and 16 Isometric views of part of a side rail with the third embodiment of an extended spring mat suspension wire according to 14 ;
• 17 a schematic cross-sectional representation through a side rail of a backrest to explain the crash forces acting on the side rail in the event of a rear crash;
• 18 a schematic cross-sectional representation of the side rail according to 17 with the main effect contour of the extended suspension wire entered therein according to 14 until 16 ;
• 19 a cut along the line A - A according to 7 in a fourth embodiment of an extended spring mat hanging wire with two parallel diagonal legs, a sheath encompassing the parallel diagonal legs and a hanging hook for hanging the extended spring mat hanging wire in an opening in the side part of the side rail;
• 20 and 21 Isometric views of part of a side rail with the fourth embodiment of an extended spring mat suspension wire according to 19 ;
• 22 a schematic perspective representation of a backrest frame and a hanging point in a side rail for the spring mat;
• 23 a schematic perspective view of part of the side rail 22 with hanging wire extension guided in a loop;
• 24 a schematic cross section through the side rail 23 and the hanging wire extension that runs downwards in a loop;
• 25 a schematic perspective representation of a backrest frame with a steel cable integrated into a cross member of the backrest frame and connecting the side rails and
• 26 a schematic perspective representation of a backrest frame with a combination of a steel cable integrated into a cross member of the backrest frame, connecting the side rails, and a hanging wire extension for the spring mat inserted into the side rails.

1 shows a perspective or isometric view of a backrest of a motor vehicle seat, with the one-piece or multi-part backrest frame 1 of the backrest being shown, which is composed of two parallel, approximately vertically extending side rails 11, 12 and an upper crossbar or an upper cross member 13, which connects the upper ends of the two side bars 11, 12 with one another and has openings 14 for the passage of support rods of a headrest. The side bars 11, 12 have a cross-sectional profile with a U- or L-shaped inner contour with a side part 30, which is essentially aligned in the vehicle longitudinal direction or if necessary, an end bevel 34 ( 3A until 3C ) and a bend or fold 32 on the front edge of the side part 30 and openings 33 in the side part 30. Instead of the bend 32 provided on the front edge of the side part 30, a front transverse part protruding approximately at right angles from the side part 30 can also be provided and instead of the openings 33 In the side part 30, eyelets can be arranged on the inside of the side part 30.

A spring mat 2 is suspended in the side rails 11, 12, which consists of longitudinal and transverse wires and is suspended into the openings 33 or eyelets in the side rails 11, 12 via suspension springs 8 and suspension wires 4. The spring mat 2 carries a cushion body, which generally also covers the backrest frame 1.

At the lower end, the backrest frame 1 is pivotally connected to the seat side parts 17 of a seat base frame of the motor vehicle seat via a pivot axis and side swivel fittings 16, so that the backrest can be adjusted in inclination about the pivot axis relative to the seat base frame.

In the event of a rear-end crash, there is a risk that the upper body of a vehicle occupant sitting on the motor vehicle seat hitting the backrest will lead to a deformation of the backrest frame 1 and even a bending of the side rails 11, 12 of the backrest frame. In particular, a bending of the side bars 11, 12 poses the risk of serious injuries to the vehicle occupant, whose upper body is no longer supported by the backrest in the upper area. The area of the side rails 11, 12 of a backrest frame 1 that is at risk of bending depends on the dimensions of the backrest frame and is generally located in the middle area between the swivel fittings 16 and the upper crossbar 13. An exact analysis to determine the bending point can be carried out through crash tests Using standardized dummy sizes can be determined. In the schematic representation of the 1 is the area of the backrest frame 1 that tends to bend due to the in 1 marked arrows KB.

2 shows a schematic perspective view of the in 1 backrest frame 1 shown before a crash load with side rails 11, 12 turned away from the outside after a crash load, as a result of which the front edges 32 of the outwardly turned side parts 30 of the side rails 11, 12 are further apart from one another at the kinks KS than in the initial state 1 . In this state, the side bars 11, 12 are no longer aligned essentially parallel to one another and the side parts 30 are no longer in the XZ plane of the motor vehicle coordinate system as in the original state.

In addition to a significant deformation of the backrest frame 1, in particular of the upper cross member 13, the result is a strong reduction in the stability of the strength structure of the side bars 11, 12, so that people or objects behind the backrest are not intercepted by the backrest, but rather fall onto them largely unbraked vehicle occupants sitting on the vehicle seat.

In the 3A until 3C the effect of a rear crash on the change in cross-section of the side rails 11, 12 of the backrest frame 1 is shown schematically.

3A shows the initial cross section of a side rail with the side part 30 with a bend or fold 32 on the front edge of the side part 30 and the transverse part 31, which is angled approximately at a right angle from the rear edge of the side part 30, with a fold 34 immediately before a rear crash, ie at a time t = 0 ms. At a time t = 70 ms after the rear crash occurs, according to 3B a minimally deformed cross section of the side rail of the backrest frame 1 as a result of the crash force K acting on the rear cross part 31 or the fold 34 of the rear cross part 31, which is indicated schematically by an arrow marked on the cross part 31. Up to this deformation, the side rail can still be described as stable. After a further 10 ms, ie at a time t = 80 ms after the rear crash, there is a strongly deformed cross section in which the side rail of the backrest frame 1 becomes unstable and bends as a result of the crash forces K acting on the side rail and marked by the arrows.

The optimal design of a component for increasing the axial moment of inertia of the cross section of a side rail 11, 12 therefore essentially depends on the initial point of the bend, which can be determined by analyzing FEM data. If such an analysis is not possible or intended, a large component 5 can be inserted into the inner contour of the side bars 11, 12, which extends from the upper cross bar 13 to the swivel fittings 16, ie the articulation of the backrest on the seat base. This large-area component 5 is supported on the edge boundaries, ie on the bend 32 of the front edge of the side part 30 and the rear cross part 31, whereby a significant increase in the axial area moment of inertia and thus an increase in the buckling force F leading to a bending of the side bars 11, 12 _k leads.

If the kink point is known, instead of a large component 5 that fills the entire inner contour of the side rails 11, 12, a small component 6 can be inserted in a form-fitting manner at the determined kink point, which corresponds accordingly 5 between the bend 32 of the front edge of the side part 30 and the rear transverse part 31, which is angled approximately at right angles to the side part 30, and thus the opposite to a bend Endangered area of the side rails 11, 12 is effectively reinforced.

In the 6A until 6C is the effect of a rear crash on the change in cross-section of the vehicle with an anti-buckling element according to the 4 and 5 provided side rails 11, 12 of the backrest frame 1 shown schematically.

The in 6A The initial cross section shown at t = 0 ms, ie immediately before the rear crash, shows the undeformed cross-sectional profile of the side rail with the side part 30, the transverse part 31, which is angled approximately at a right angle from the rear edge of the side part 30, with the end bevel 34 and the offset 32 on the front edge of the side part 30. After a period of t = 70 ms, an arrow appears due to the force acting on the side rail 6B marked force K has a minimally deformed cross section, with the side rail still being stable up to this deformation. After another 10 ms, ie at a time t = 80 ms after the rear crash, according to 6C a cross-section that continues to be only minimally deformed, ie the side rail remains stable despite increasing load due to the force K.

The effectiveness of components that are positively integrated into the side rails 11, 12 as anti-buckling elements is based on the fact that the components greatly reduce or maximally limit a change in the moment of resistance of the side rails 11, 12 under dynamic crash loads, the limitation being in the main resistance axis of the side rails 11, 12 takes place.

Preferred embodiments for increasing the buckling resistance of the side rails 11, 12 and thus the backrest frame 1 of the backrest of a motor vehicle seat are described below with reference to 7 until 24 explained.

Instead of a flat component as an anti-kinking element as in the embodiments according to 4 and 5 an existing component is used, namely the hanging wire 4 of the spring mat 2 according to 1 . The hanging wire 4 is selected, which is located in the area KB of the side rails 11, 12 that is at risk of kinks 1 is located, whereby if the hanging wire is arranged differently, 4 measures are taken to relocate the hanging areas into the area of the potential kinks according to 22 until 24 can be provided.

The hanging wire 4 is extended for this purpose and, if necessary, without using the hanging spring 8 according to the top view 7 between the vertical wires of the spring mat 2 and the hanging point, ie the opening 33 or hanging eyes provided in the side rails 11, 12.

The type and shape of the extension of the suspension wires to form anti-kink elements, the diverse options for supporting the extended suspension wires in the side rails and their connection to the side rails lead to a variety of embodiments.

A first embodiment with only a short extension of a suspension wire 4 is shown in the isometric views 8th until 10 shown, where 8th a cut along the line A - A according to 7 and the 9 and 10 show isometric views of the first embodiment from different viewing directions.

• - einen Verbindungsschenkel 40, der von der Federmatte 2 zu einer durch den Eckbereich von Seitenteil 30 und Querteil 31 der Innenkontur des Seitenholms 11, 12 gebildeten Abstützung geführt ist,
• - eine sich am hinteren Querteil 31 oder dem Eckbereich von Seitenteil 30 und Querteil 32 abstützende, durch Abwinklung gebildete Abstützkante 41,
• - einen sich entlang zumindest eines Teils des Seitenteils 30 erstreckenden ersten Längsschenkel 42,
• - einen vom ersten Längsschenkel 42 abgewinkelten Einhängehaken 44, der in die Öffnung 33 oder Öse im Seitenteil 30 des Seitenholms 11, 12 eingehängt ist und nach einer 180°-Abwinklung zurückgeführt ist,
• - einen parallel zum und dicht neben dem ersten Längsschenkel 42 geführten zweiten Längsschenkel 43 und
• - einen vom zweiten Längsschenkel 43 abgewinkelten Endschenkel 48, der im Eckbereich von Seitenteil 30 und Querteil 31 abgestützt ist,

auf.In the first embodiment, the extended suspension wire 4

• - a connecting leg 40, which is guided from the spring mat 2 to a support formed by the corner region of the side part 30 and cross part 31 of the inner contour of the side rail 11, 12,
• - a support edge 41 formed by bending on the rear cross part 31 or the corner area of the side part 30 and cross part 32,
• - a first longitudinal leg 42 extending along at least part of the side part 30,
• - a hanging hook 44 angled from the first longitudinal leg 42, which is hooked into the opening 33 or eyelet in the side part 30 of the side rail 11, 12 and is returned after a 180 ° bend,
• - a second longitudinal leg 43 and guided parallel to and close to the first longitudinal leg 42
• - an end leg 48 angled from the second longitudinal leg 43, which is supported in the corner area of the side part 30 and cross part 31,

on.

The effectiveness of the extended suspension wires 4, which are positively integrated into the side rails 11, 12 as anti-kinking elements, is based on the fact that the extended suspension wires 4 greatly reduce or maximally limit a change in the moment of resistance of the side rails 11, 12 under dynamic crash loads, the limitation being in the Main axis of resistance of the side rails 11, 12 takes place.

dargestellt werden kann, worin E das Elastizitätsmodul des verwendeten Materials für den Einhängedraht, I das axiale Flächenträgheitsmoment des Drahtquerschnittes und s die sogenannte „Knicklänge“ ist, die mit der Länge des Stabes L in der Beziehung $$s=\beta \cdot L$$

The mathematical determination of the force required to buckle the side rails 11, 12 and thus the buckling resistance of the side rails 11, 12, taking into account the geometric, mechanical and material parameters of the loaded side rails 11, 12, is based on Euler's stability theory with regard to the buckling of slender rods with different boundary conditions and a centrally acting compressive force, after which the buckling force for the elastic region is given by the formula $$F_k=\frac{{\pi }^{2}EI}{s^2}$$

can be represented, where E is the modulus of elasticity of the material used for the suspension wire, I is the axial moment of inertia of the wire cross section and s is the so-called “buckling length”, which is related to the length of the rod L $$s=\beta \cdot L$$

Stands, whereby the buckling length coefficient β for the case of a rod clamped on one side, which corresponds to the design of a backrest of a motor vehicle seat, is β = 2.

To dimension the extended suspension wire 4 used as an anti-buckling element, the acting crash force and the free bending length of the suspension wire 4 must be taken into account. If one assumes the acting crash force to be F _k = approx. 2,000 N, then taking into account the elasticity modulus for steel wire with a diameter of 2.5 mm and a length of 24 mm for the extended hanging wire, a buckling force of F _k = results in accordance with the above equation 1,769 N, so that the extended suspension wire 4 with two parallel longitudinal legs 42, 43 and a U-shaped bend absorbs a buckling force of 2 × 1,769 N = 3,538 N.

To further increase the buckling force to be absorbed by the extended suspension wire 4, the two parallel longitudinal legs 42, 43 of the suspension wire 4 can be arranged in a sleeve.

A second embodiment is according to 11 until 13 designed in the manner of a truss, whereby 11 a cut along the line A - A according to 7 and the 12 and 13 show isometric views of the second embodiment from different viewing directions.

• - einen Verbindungsschenkel 40, der von der Federmatte 2 ausgehend abgewinkelt zu einer vom Seitenteil 30 der Innenkontur entfernten Abkantung 34 des hinteren Querteils 31 geführt ist,
• - eine sich am hinteren Querteil 31 oder dem Eckbereich von hinterem Querteil 31 und Abkantung 34 des hinteren Querteils 31 abstützende, durch Abwinklung gebildete Abstützkante 41,
• - einen ersten Diagonalschenkel 45, der von der Abstützkante 41 diagonal zur Öse oder Öffnung 33 des Seitenteils 30 geführt ist,
• - einen Einhängehaken 44, der in die Öse oder Öffnung 33 des Seitenteils 30 eingehängt ist,
• - einen Längs- oder Diagonalschenkel 47, der sich vom Einhängehaken 44 entlang des Seitenteils 30 oder schräg zum Seitenteil 30 zu dem zwischen dem Seitenteil 30 und dem hinteren Querteil 31 gebildeten Eckbereich erstreckt und
• - einen vom Längs- oder Diagonalschenkel 47 abgewinkelten Endschenkel 48, der im Eckbereich von Seitenteil 30 und Querteil 31 abgestützt ist,

auf.In this second embodiment, the extended suspension wire 4

• - a connecting leg 40, which is guided at an angle from the spring mat 2 to a fold 34 of the rear cross part 31 which is remote from the side part 30 of the inner contour,
• - a support edge 41 which is supported on the rear cross part 31 or the corner area of the rear cross part 31 and fold 34 of the rear cross part 31 and is formed by an angle,
• - a first diagonal leg 45, which is guided from the support edge 41 diagonally to the eyelet or opening 33 of the side part 30,
• - a hanging hook 44 which is hooked into the eyelet or opening 33 of the side part 30,
• - a longitudinal or diagonal leg 47, which extends from the hanging hook 44 along the side part 30 or obliquely to the side part 30 to the corner area formed between the side part 30 and the rear cross part 31 and
• - an end leg 48 angled from the longitudinal or diagonal leg 47, which is supported in the corner area of the side part 30 and cross part 31,

on.

• - einen Verbindungsschenkel 40, der von der Federmatte 2 ausgehend abgewinkelt zu einer vom Seitenteil 30 der Innenkontur entfernten Abkröpfung des hinteren Querteils 31 geführt ist,
• - eine sich am hinteren Querteil 31 und der Abkröpfung des hinteren Querteils 31 abstützende, durch Abwinklung gebildete Abstützkante 41,
• - einen ersten Diagonalschenkel 45, der von der Abkröpfung diagonal zu der Öse oder Öffnung 33 des Seitenteils 30 geführt ist,
• - einen Einhängehaken 44, der in die Öse oder Öffnung 33 des Seitenteils 30 eingehängt ist,
• - einen zweiten Diagonalschenkel 49, der parallel zum ersten Diagonalschenkel 45 geführt ist und
• - einen vom zweiten Diagonalschenkel 49 abgewinkelten Endschenkel 48, der im Eckbereich von Seitenteil 30 und Querteil 31 abgestützt ist,

auf.In a third, in the 14 until 16 illustrated embodiment, where 14 a cut along the line A - A according to 7 and the 15 and 16 isometric views of the third embodiment from different viewing directions show the extended suspension wire 4

• - a connecting leg 40, which is angled from the spring mat 2 to a bend in the rear cross part 31 that is remote from the side part 30 of the inner contour,
• - a support edge 41 formed by an angle and supported on the rear cross part 31 and the bend of the rear cross part 31,
• - a first diagonal leg 45, which is guided from the bend diagonally to the eyelet or opening 33 of the side part 30,
• - a hanging hook 44 which is hooked into the eyelet or opening 33 of the side part 30,
• - a second diagonal leg 49, which is guided parallel to the first diagonal leg 45 and
• - an end leg 48 angled from the second diagonal leg 49, which is supported in the corner area of the side part 30 and cross part 31,

on.

Based on this third embodiment, the functional principle of the design of suspension wires 4 of the spring mat 2 as anti-kink elements and the advantages that can be achieved compared to flat anti-kink elements will be explained.

First of all, when using extended suspension wires 4 as anti-kink elements, only an extension of the lateral suspension contour of the spring mat 2 is required, without having to produce an additional component and mount it in the side rails 11, 12, so that the use of suspension wires 4 as anti-kink elements Articulated elements do not require any additional assembly process.

17 shows a schematic cross section of the spring mat 2 of a motor vehicle seat in relation to the upper body of a vehicle occupant located on the motor vehicle seat, as well as a side rail which is L-shaped in cross section with the side part 30, the transverse part 31 which is angled approximately at right angles from the rear edge of the side part 30, and the offset 32 on the front edge of the side part 30.

In the event of a rear-end crash, the upper body of the vehicle occupant exerts a pushing movement on the spring mat 2 in the direction of the arrow K1, i.e. H. the upper body of the vehicle occupant penetrates into the spring mat 2, so that the spring mat 2 is pressed against the direction of travel of the motor vehicle indicated by the arrow FR in the direction of the arrow K2 in the direction of the rear of the motor vehicle. At the same time, the spring mat 2 pulls the side part 30 inwards according to the arrow K3. This force diagram results in a total force K4, which is directed from the side part 30 to the bend of the rear cross part 31.

18 shows the main direction of action W according to the 14 until 16 trained extended suspension wire 4 as an anti-kink element. The extension of the suspension wire 4 of the spring mat 2 thus follows the resulting force vector K4 13 in the event of a rear crash and aims at the optimal support area of the side rail 11, 12, ie the pushing movement of the spring mat 2 as a result of the penetration of the upper body of the vehicle occupant into the spring mat 2 thus simultaneously acts as an amplification of the counterforce that the extended suspension wire designed as an anti-kinking element 4 for changing the edge of the side rail 11, 12 of the backrest frame 1.

By minimizing or preventing the buckling of the side rails 11, 12 by increasing the buckling resistance of the side rails as a result of the extended suspension wires 4 specifically integrated into the side rails, it is therefore possible to design the side rails with minimal wall thickness and/or from a material of lower specific weight , which leads to a significant weight advantage.

A fourth embodiment of the design of extended suspension wires 4 as an anti-kink element is in the 19 until 21 presented in isometric views, where 19 a cut along the line A - A according to 7 and the 20 and 21 show isometric views of the fourth embodiment from different viewing directions.

This fourth embodiment is different from that in the 14 until 16 shown third embodiment only in that the increased buckling stability is reinforced by a sleeve 7 surrounding the diagonal legs 45, 49.

For all four above using the 7 until 21 In the exemplary embodiments described, the spring mat 2 is installed by inserting the wire contour of the extended suspension wires 4 into the rear area of the side rails 11, 12, ie in the area between the side part 30 and the rear cross part 31 of the side rails 11, 12 and hooking the suspension hook 44 the extended suspension wires 4 in the final assembly position into the corresponding opening 33 of the side rails 11, 12 or into an eyelet formed in the side rails 11, 12.

Since the optimal effect of the extended hanging wires is only given if they are arranged at the previously determined, vulnerable kink points specific to the respective backrest frame, the respective spring mats suspended in the backrest frame must be modified according to the analyzed kink points. 22 shows a schematic perspective view of a backrest frame 1 with a suspended spring mat 2 and an extended hanging wire 4, which opens into the side rail 11, 12 above the vulnerable bend point. In order to achieve the optimal effect of the extended hanging wire 4, the hanging point must either be pushed down a little to the level of the area of the potential kink point or correspondingly 23 and 24 be guided downwards in a loop 9. This shows 23 in a schematic perspective view, the loop-shaped guidance of the extended suspension wire 4 in the side rail 11, 12 and 24 in a schematic cross-sectional representation the course of the loop 9 in relation to the side rail 11, 12, which is L-shaped in cross section.

A further or alternative measure to increase the effect of extended suspension wires as anti-kink elements in side rails of backrest frames is to at least partially encapsulate the suspension wires with a plastic in the area running in the inner contour of the side rails, so that not only parallel legs of the Suspension wires are surrounded with a sleeve to increase the kink resistance, but rather the entire area of the extended suspension wire within the inner contour of the side rails is stabilized by the plastic overmolding, the plastic overmolding preferably resting on at least one support of the inner contour of the side rails.

The use of extended suspension wires as anti-kink elements in side rails of backrest frames can be done with or without tension springs between the side rails and the spring mat.

25 shows in one of the perspective illustrations 4 Corresponding representation of the backrest frame 1 with the omission of the spring mat 2, the integration of a tension strut designed as a steel cable 10 into a cross part 15 connected to the side rails 11, 12. The steel cable 10 is connected to fastening parts 18, 19 of the side rails 11, 12, which may be included Additional reinforcing or force distribution elements are also suitable for absorbing high tensile forces and tensions. To integrate the steel cable 10 into the strength structure of the backrest or into the backrest frame 1 and to prevent the steel cable 10 from springing forward into the backrest upholstery in the event of a crash, the steel cable 10 is guided through openings 151, 152 in the cross strut 15 and connected to the fastening points 18, 19 of the Side rails 11, 12 connected.

In the event of a crash, the steel cable 10 braces the side bars 11, 12 together and thus prevents the side parts 30 of the side bars 11, 12, which in the initial state are aligned essentially parallel to the longitudinal extent of the motor vehicle in the XZ plane of the motor vehicle coordinate system, from breaking away.

To adjust the tension of the steel cable 10, either the length of the steel cable 10 can be dimensioned to the length required in the event of a crash for the deformation-free connection of the side rails 11, 12 or it can be adjusted using a turnbuckle integrated into the steel cable 10.

As an alternative to using a steel cable 10 as a tension strut between the side rails 11, 12, a tension plate that can be subjected to tensile force or several steel cables that are separated from one another or combined into a cable bundle can be used, which develop a redundancy effect in the event of a crash.

26 shows a schematic perspective view of a backrest frame 1, a combination of a steel cable 10 integrated into a cross strut 15 of the backrest frame 1, connecting the side rails 11, 12 via fastening points or parts 18, 19 of the side rails 11, 12 and guided in a loop and in Hanging points of the side rails 11, 12 inserted and at support points of the side parts 30 and / or the cross parts 31 of the side rails 11, 12 supporting extended suspension wires 4 for the spring mat 2 to achieve a high kink resistance of the backrest frame 1 without a significant increase in material and manufacturing costs and the weight of a motor vehicle seat.

Both measures serve to significantly increase the stability of the side rails 11, 12 in the the spring mat 2 increases the stability of the side rails 11, 12 in the , 12 outwards and resulting in a kink in the backrest frame 1, without requiring an increase in the area moment of resistance of the side rails by increasing the cross-sectional area of the side rails and an increase in weight as well as increased material and manufacturing costs for the backrest frame. To increase the stability or support of the strength structure of the side rails 11, 12 and thus of the backrest frame 1 by reinforcing the cross-sectional profile of the side rails 11, 12, the extended suspension wires 4 are pushed into the area of the potential kink point or accordingly 23 and 24 looped up or down.

Reference symbol list

1

Backrest frame

2

Feather mat

4

Hanging wire

5

large-scale component

6

small component

7

sleeve

8th

Suspension spring, tension spring

9

Ribbon

10

tension strut

11, 12

Side rails

13

Crossbar or upper crossbar

14

openings

15

Cross brace

16

Swivel fittings

17

Seat side panels

18, 19

Fastening parts/locations

30

Side part

31

rear cross section

32

Offset or bend

33

opening

34

folding

40

connecting leg

41

Support edge

42

first longitudinal leg

43

second longitudinal leg

44

Hanging hooks

45

first diagonal leg

47

Longitudinal or diagonal legs

48

end leg

49

second diagonal leg

151, 152

openings

KB

area at risk of kinks

KS

kink

F↓k↓

buckling force

K

Crash force

K1, K2, K3

Forces

K4

Total strength

FR

Direction of travel

W

Main direction of action

Claims (27)

Backrest of a motor vehicle seat with • a rigid, load-bearing backrest frame (1) made of • at least one upper crossbar (13), • two side bars (11, 12) ◯ with mutually facing, profiled inner contours and a spring mat (2) suspended in the backrest frame (1). ), which supports an upholstered body, wherein ◯ the side rails (11, 12) are connected to a component (4, 5, 6; 10) which increases the buckling resistance of the side rails (11, 12), characterized in that the inner contours of the side rails ( 11, 12) are U- or L-shaped in cross section with a side part (30) aligned parallel to the longitudinal direction of the motor vehicle (X direction of the motor vehicle coordinate system) and at least one transverse part (31) angled from the side part (30) and that Component (4, 5, 6) extends at least partially diagonally to the side part (30) and the at least one transverse part (31) and is supported on supports of the side part (30) and / or the at least one transverse part (31). backrest Claim 1 , characterized in that the component (4, 5, 6; 10) which reinforces the buckling resistance of the side rails (11, 12) in order to support the structure of the backrest frame (1) or to hold the side rails (11, 12) in position, the moment of resistance of the side bars (11, 12) increases in the direction of the X-axis of the motor vehicle. backrest Claim 1 or 2 , characterized in that at least in part of the inner contour of the side rails (11, 12) there is a component (4, 5, 6) which increases the buckling resistance of the side rails (11, 12) in the longitudinal direction of the motor vehicle (X direction of the motor vehicle coordinate system). is inserted in a form-fitting manner. backrest Claim 3 , characterized in that a large component (5) is positively inserted into the inner contour of the side rails (11, 12) over the entire length of the side rails (11, 12). backrest Claim 3 , characterized in that a component (6) with a smaller area compared to the surface of the side rails (11, 12) is inserted in a form-fitting manner into the inner contour of the side rails (11, 12) on at least one section of the side rails (11, 12) that is at risk of buckling . Backrest according to one of the preceding claims, characterized in that the supports on - the corner areas between the side part (30) and the at least one cross part (31) and / or - on folds (34) or bends (32) of the side part (30) and/or the at least one transverse part (31) and/or - are formed on catch beads of the side part (30) and/or the at least one transverse part (31). Backrest according to at least one of the preceding claims, characterized in that the component is formed from extended suspension wires (4) of the spring mat (2). backrest Claim 7 , characterized in that the suspension wires (4) guided along at least part of the side part (30) and / or diagonally to the side part (30) and rear cross part (31) of the inner contour of the side bars (11, 12) are supported on at least one support and are suspended in an eyelet or opening (33) in the side part (30) of the side bars (11, 12). backrest Claim 7 or 8th , characterized in that the extended hanging wire (4) - a connecting leg (40), which is formed by the corner area of the side part (30) and cross part (31) of the inner contour of the side rail (11, 12) from the spring mat (2). Support is guided, - a support edge (41) which is supported on the rear cross part (31) or the corner area of the side part (30) and cross part (31) and is formed by bending, - a first which extends along at least part of the side part (30). Longitudinal leg (42), - a hanging hook (44) angled from the first longitudinal leg (42), which is hooked into the opening (33) or eyelet in the side part (30) of the side rail (11, 12) and returned after a 180 ° bend - a second longitudinal leg (43) guided parallel to and close to the first longitudinal leg (42) and - an end leg (48) angled from the second longitudinal leg (43) and supported in the corner area of the side part (30) and cross part (31). is, has. backrest Claim 9 , characterized in that the connecting leg (40) has a first section aligned parallel to the spring mat (2) and a second section angled from the first section and leading to the support edge (41). backrest Claim 10 , characterized in that the first and second longitudinal legs (42, 43) of the suspension wire (4) are arranged in a sleeve. backrest Claim 7 or 8th , characterized in that the extended suspension wire (4) - a connecting leg (40) which is angled from the spring mat (2) to a fold (34) of the rear cross part (31) which is remote from the side part (30) of the inner contour, - a support edge (41) formed by bending which is supported on the rear cross-section (31) or a corner area of the rear cross-section (31) and fold (34) of the rear cross-section (31), - a first diagonal leg (45) which is formed by the Support edge (41) is guided diagonally to the eyelet or opening (33) of the side part (30), - a hanging hook (44) which is hooked into an eyelet or opening (33) of the side part (30), - a diagonal or longitudinal leg ( 47), which extends from the hanging hook (44) along the side part (30) or diagonally to the side part (30) to the corner area formed between the side part (30) and the rear cross part (31) and - one of the diagonal or longitudinal legs ( 47) angled end leg (48), which is supported in the corner area of the side part (30) and cross part (31). backrest Claim 12 , characterized in that the connecting leg (40) has a first section aligned parallel to the spring mat (2) and a second section running parallel to the fold (34) of the rear transverse part (31). backrest Claim 7 or 8th , characterized in that the extended hanging wire (4) - a connecting leg (40), which is angled from the spring mat (2) to a bend in the rear cross part (31) remote from the side part (30) of the inner contour, - a on the rear cross part (31) and the fold (34) of the rear cross part (31), which is formed by bending, supporting edge (41), - a first diagonal leg (45), which extends diagonally from the fold (34) to an eyelet or opening ( 33) of the side part (30), - a hanging hook (44), which is hooked into the eyelet or opening (33) of the side part (30), - a second diagonal leg (49), which is parallel to the first diagonal leg (45) is guided and - has an end leg (48) angled from the second diagonal leg (49), which is supported in a corner area of the side part (30) and rear cross part (31). backrest Claim 14 , characterized in that the first and second diagonal legs (45, 49) are arranged in a sleeve (7). Backrest according to at least one of the previous ones Claims 9 until 15 , characterized in that the hanging hook (44) is formed from a back and forth movement of a hanging leg folded through 180 °. Backrest after at least one of the Claims 7 until 16 , characterized in that the suspension wires (4) are at least partially in the inner contour of the side rails (11, 12) running area are encapsulated with a plastic. backrest Claim 17 , characterized in that the plastic coating rests on at least one support. Backrest after at least one of the Claims 7 until 18 , characterized in that the extended suspension wires (4) are connected to the spring mat (2) via a tension spring (8). Backrest according to at least one of the preceding claims, characterized by a tension strut (10) which connects the side bars (11, 12) and can be subjected to tensile force. backrest Claim 20 , characterized in that the ends of the tension strut (10) are connected to hooks or eyelets (18, 19) of the side bars (11, 12). backrest Claim 20 or 21 , characterized in that the tension strut (10) consists of at least one steel cable. backrest Claim 22 , characterized in that the pretension of the steel cable for connecting the side rails (11, 12) can be changed by changing the cable length. backrest Claim 22 , characterized by a turnbuckle integrated into the steel cable for changing the cable length, by actuating which the cable ends of the steel cable are moved towards one another or removed from one another. backrest Claim 20 , characterized in that the tension strut (10) consists of a steel sheet. Backrest according to one of the previous ones Claims 20 until 25 , characterized in that the tension strut (10) is integrated into the spring mat (2). Backrest according to one of the previous ones Claims 20 until 26 , characterized in that the tension strut (10) is connected to the fastenings of the spring mat (2) on the side rails (11, 12).

Images