Safety belt for a safety belt assembly for a motor vehicle

Abstract

The invention relates to a safety belt (1) for a safety belt device of a motor vehicle, the safety belt comprising at least one hollow portion (14), the at least one hollow portion having at least one cavity (5) for accommodating electronic components and / or circuits, wherein the cavity (5) is formed by two fabric layers (6, 7), and the fabric layers (6, 7) are formed by a plurality of warp threads (11) and weft threads (10). The fabric layers (6, 7) are connected to each other in the outer edge portions (3, 4) by edge braiding threads (12). A single-layer portion (15) adjoins the at least one hollow portion (14), in which the fabric layers (6, 7) are connected to each other by a plurality of central braiding threads (13), and the central braiding threads (13) in the hollow portion (14) are braided together in only one of the fabric layers (6, 7).

Description

[0001] The invention relates to a seat belt for a seat belt arrangement of a motor vehicle.

[0002] In general, a seat belt in a seat belt arrangement of a motor vehicle is used to restrain an occupant in the motor vehicle in the event of an accident in order to optimally prevent more serious injuries. The seat belt arrangement has, in particular, a seat belt retractor fastened in a manner fixed to the vehicle, which has a seat belt reel, on which one end of the seat belt can be wound. The other end of the seat belt can be locked by a seat belt tongue in a seat belt buckle fastened in a manner fixed to the vehicle, or likewise permanently fixed to the vehicle by an end fitting. In the case of the other end being fastened in a fixed manner to the vehicle by an end fitting, the seat belt arrangement also has a seat belt tongue guided movably on the seat belt, which seat belt tongue can be locked in a seat belt buckle fastened to the vehicle, for example to form a three-point geometry of the seat belt.

[0003] Due to its purpose of restraining occupants, the seat belt itself must meet various requirements in terms of tensile strength, surface finish, edge condition, etc.

[0004] Modern motor vehicles are also equipped with a large number of electronic components, such as sensors, actuators, monitors, acoustic units, heating and cooling devices, etc., which are expected to increase further as motor vehicles and their drive units, control units and comfort devices become increasingly automated. These devices must furthermore be connected to each other and to corresponding power supplies and control devices via electrical lines. Insofar as such electronic components and lines are part of a seat belt device, they must be arranged accordingly on the seat belt device without impairing the use or function of the seat belt device.

[0005] According to DE 10 2011 009 318 A1, it is known to provide a safety belt with a hose section which extends in the longitudinal direction of the safety belt and into which electronic components can be introduced. No further details on how to produce the hose section in the safety belt can be found in this publication.

[0006] Against this background, the object of the present invention is to provide a seat belt for a seat belt arrangement of a motor vehicle, which seat belt has a cavity for accommodating electronic components and circuits, which cavity is as simple as possible in design and can be manufactured cost-effectively.

[0007] According to the present invention, a safety belt is proposed to achieve this object. Further preferred improvements will be understood from the drawings and the accompanying description.

[0008] According to the basic idea of ​​the present invention, it is proposed that the cavity formed in the hollow part of the safety belt is formed by two fabric layers, which are connected to each other in the outer edge part by one or more edge braiding lines extending parallel to the longitudinal direction of the safety belt. The hollow part is not continuous over the entire length of the belt; instead, the hollow part is adjacent to at least one single-layer part. The single-layer part is formed by the same fabric layers as the hollow part, which are respectively woven continuously from multiple warp and weft threads. The edge braiding lines also extend continuously in the hollow part and the single-layer part. Therefore, a plurality of central braiding lines extending parallel to the longitudinal direction of the safety belt are provided in the central area arranged between the edge parts, which central braiding lines connect the fabric layers to each other in the single-layer part and are woven together only in one fabric layer in the hollow part.

[0009] By the achievement according to the present invention, the cavity can be manufactured when the safety belt is woven. In its basic structure, the safety belt is woven by two independent fabric layers, which are only connected to each other by edge braiding wires in the hollow area of ​​the edge part. In the single-layer part, the fabric layers are connected to each other by edge braiding wires and center braiding wires over the entire width of the safety belt, and in the hollow part, the center braiding wires extend in one fabric layer, so that a cavity can be formed between the fabric layers. Therefore, the connecting wires for connecting the two fabric layers can be woven in at the same time when weaving, so that the connection of the fabric layers can be directly realized when weaving, and no separate working steps are required to connect the fabric layers. Because the braiding wire is only used to connect the two fabric layers, but the tension acting in the constraint situation is absorbed by the warp as described above, it is sufficient to design and arrange the braiding wire only from the perspective of the reliable connection of the two fabric layers. Therefore, the yarn thickness of the fabric layer, the yarn thickness of the tie wire, the material of the braiding yarn and the number of the braiding yarns can be used as the design parameters for the connection of the fabric layers. Because not the entire area of ​​the seat belt is formed as a hollow portion, but for example a plurality of short hollow portions can be alternated with single-layer portions, cavities can be provided only in the area of ​​the seat belt where electronic functions are required. This also improves the retraction and restraint performance of the seat belt device.

[0010] According to the present invention, it is proposed that the fabric layer is formed by a plurality of warp threads and weft threads. The warp threads extend in the longitudinal direction of the safety belt and are interconnected by the weft threads to form a flat fabric. Therefore, the warp threads form the surface of the fabric layer in the finished woven fabric, while the weft threads extend between the warp threads and are not visible from the outside when the fabric is quite dense. The warp threads are designed to have a corresponding tensile strength and are used to absorb the tension in the longitudinal direction of the safety belt, while the weft threads are thinner and are used to hold the warp threads together.

[0011] It is also proposed that the safety belt has a width of 40 mm to 50 mm, preferably 46 mm to 48 mm, and that the fabric layers are connected to each other by braiding threads in edge sections, which edge sections each have a width of at least 2 mm, preferably at least 4 mm. The width of the proposed safety belt corresponds to the standard safety belt width. By the proposed dimensioning of the edge sections, it is possible to prevent the safety belt from losing its planar shape under the action of shear forces and thus forming wrinkles in the safety belt. In particular, it is thereby possible to prevent a safety belt with two fabric layers from twisting or buckling when the edge sections are laterally unfolded in the longitudinal direction. Therefore, the width of the edge sections and the associated planar connection of the fabric layers in the edge sections can be achieved in particular by correspondingly selecting the number and arrangement of the braiding threads.

[0012] It is also proposed that the hollow portion has a length of 1300 mm to 1700 mm and that the cavity arranged in the hollow portion has a width of 10 mm to 37 mm. By the proposed dimensioning of the cavity width, the cavity can be adapted to the application employed, so that, for example, the dimensions of the cavity for wiring electrical lines can be designed to be very narrow. According to the standard, the seat belt in the seat belt device of a motor vehicle is 3500 mm long. Due to the preferred length range of the hollow portion, the seat belt can be given functionality only in the required area.

[0013] It is further proposed that a portion of the seat belt is a single-layer portion, which is arranged in the region of a deflector or a seat belt tongue in a seat belt device of a motor vehicle in the worn state or is wound on a seat belt retractor after unbuckling. The proposed improvement improves the retraction and restraint properties of the seat belt device. In principle, the single-layer portion has the advantage that no fabric layers are provided that are superimposed on each other and can slide relative to each other, as is the case with hollow portions. Therefore, with a single-layer portion, the likelihood of the seat belt twisting is significantly reduced and the seat belt can be wound on the reel into a more compact, wrinkle-free belt roll. Therefore, under the action of lateral forces, the seat belt also does not form ripples in the deflection area and the deflector area of ​​the seat belt tongue. Therefore, the single-layer portions can be formed in such a way that in these portions the seat belt is woven with a single fabric layer or two fabric layers in this portion are connected to each other in a planar manner by a braiding thread.

[0014] Therefore, the edge braiding line is preferably woven with the weft in a conventional weaving method, such as a 2 / 2 weaving method or a 4 / 4 weaving method, so that the uniform connection of the fabric layer can be achieved, with the best uniform and smooth surface structure. Therefore, the 4 / 4 weaving method should be understood as such a weaving method, wherein, due to the side switching relative to the two sheds of the two fabric layers during the weaving process, the edge braiding line is always periodically arranged on four continuous wefts on one side of the safety belt, and is arranged on the subsequent two wefts on the other side of the safety belt. Therefore, the corresponding directly adjacent edge braiding line, or even a plurality of adjacently arranged edge braiding line groups, can preferably be arranged in such a way that, in the weaving process, they are arranged on the opposite side of the shed, and are therefore arranged on the opposite side of the weft. Alternatively, the adjacent edge braiding line can also be offset by one or two wefts respectively. Therefore, since the wefts of different fabric layers are connected by braiding lines, the warps are also indirectly connected by braiding lines, so that the edge portion produces a firm combination of two otherwise independent fabric layers. In the edge portion, the close planar connection of the fabric layer is the most effective for the planar stability of the entire safety belt. In a single-layer section, the weave of the central weaving thread with the weft threads of the fabric layer can be different from the particularly stable weave of the edge weaving threads, but it still has the same effect of connecting and stabilizing the surface.

[0015] The central braiding thread in the cavity area of ​​the hollow part within one fabric layer is further preferably woven in the same weave as the warp threads belonging to this fabric layer. Thus, the fabric layer transitions continuously from the single-layer part to the hollow part without presenting any change in the appearance and touch of the surface in the cavity area. Thus, the central braiding thread changes from the weave that guides the central braiding thread through two fabric layers for connection purposes to the single-layer weave. In contrast to the edge braiding threads and the warp threads, the central braiding thread extends discontinuously at the part transition and has different periodicity and different weaving depths in the single-layer part and the hollow part, two-layer or single-layer.

[0016] It is also proposed that the warp threads are connected to the weft threads in a 7 / 1 weave. According to the above definition of the weave of the edge weaving thread, the 7 / 1 weave is understood to be a weave of warp threads and weft threads, wherein during the weaving of seven consecutive weft threads, the warp threads are arranged in a periodic sequence on one side of the shed of the fabric layer, they switch sides of the shed for the subsequent weft thread, after which they are arranged again on the other side of the shed to repeat the sequence for the next seven weft threads. By means of the proposed weaving of the warp threads and weft threads, a surface optimized in terms of haptics and friction can be obtained. Corresponding fabric layers can also be realized thereby, which can be particularly well connected to each other by means of the weaving threads using the proposed weaving method, so that cavities are formed.

[0017] In the hollow region, the two fabric layers can be further connected to each other in one or more central parts arranged between the edge parts, forming two or more cavities separated from each other. By means of the proposed additional connecting part, on the one hand, the connection of the fabric layers can be further improved, and on the other hand, a plurality of cavities separated from each other can be realized, for example, for the wiring of intentionally separated lines or the separate arrangement of electrical components. In a preferred embodiment, the hollow region can include two cavities extending in parallel in the longitudinal direction of the safety belt; the connection area of ​​the fabric layer formed between the two cavities is realized by a portion of the central braiding wire, which here does not extend only in one fabric layer with the warp braiding, but further connects the two fabric layers to each other, as in the single-layer part. Therefore, the two cavities preferably have a width of 10 mm to 18.5 mm, respectively. Another embodiment includes three cavities extending in parallel, and in the case of the same size design, the three cavities have a width of 10 mm to 12 mm, respectively. In principle, other embodiments with additional cavities are also conceivable, for example four or five cavities, but the total width of the plurality of cavities extending in parallel should not exceed the preferred maximum width of the individual cavities of 37 mm, so that the edge portions still have sufficient width for the plane stabilization of the entire seat belt. If a greater number of cavities extend in parallel, the available space for the individual cavities also becomes increasingly smaller and thus becomes ineffective, especially since no more connecting areas between the cavities are available.

[0018] The present invention is explained below using a preferred embodiment with reference to the accompanying drawings. The following is shown:

[0019] Figure 1 The safety belt according to the present invention is shown in plan view and in cross-section;

[0020] Figure 2a , Figure 2b and Figure 2c is a schematic diagram of the dimensions of a safety belt according to the present invention having one, two and three parallel extending cavities; and

[0021] Figure 3 A longitudinal section through a fabric layer of a safety belt is shown in an enlarged exploded view.

[0022] exist Figure 1 In the figure, the hollow part 14 of the safety belt 1 according to the invention is visible in the plan view and in the cross-sectional view on the right. The safety belt 1 has two fabric layers 6 and 7 which are not connected to each other in the central part 2 but are connected to each other in the two outer edge parts 3 and 4. The safety belt 1 also has a width A of 46 mm to 48 mm, while the edge parts 3 and 4 each have a width B of 2 mm, preferably 4 mm.

[0023] The safety belt 1 has a plurality of warp threads 11 extending in the longitudinal direction of the safety belt 1, and the warp threads 11 are woven with weft threads 10 extending perpendicular to the warp threads 11 to form fabric layers 6 and 7. Therefore, each of the fabric layers 6 and 7 has warp threads 11 and weft threads 10 separated from each other, so that they form fabric layers 6 and 7 independent of each other. As will be described below, the fabric layers 6 and 7 are connected to each other in the edge portions 3 and 4, so that a cavity 5 is formed between the fabric layers 6 and 7, which is bounded toward the edge side by the connection in the edge portions 3 and 4. Electrical circuits or additional electronic components (such as a smaller control or storage unit, a simple switch, a sound playback device, a heating device, etc.) can be arranged in the cavity 5.

[0024] The two fabric layers 6 and 7 are woven together by edge braiding threads 12 arranged in the edge parts 3 and 4, which form the connecting parts 8 and 9 of the fabric layers 6 and 7 in the edge parts 3 and 4. The edge braiding threads 12 do not need to span the entire width of the edge parts 3 and 4. For example, in the case where special braiding is provided in the edge area of ​​the safety belt 1 to achieve an edge that is as soft as possible, the edge braiding threads 12 in the outer edge areas of the edge parts 3 and 4 can also be omitted, as long as this is not disadvantageous for the connection of the fabric layers 6 and 7. A central braiding thread 13 is provided in the central area 2, but in the hollow area 14 shown here, this central braiding thread does not contribute to the connection of the fabric layers 6 and 7, but is only woven into the fabric layer 6 or 7 to achieve the formation of the cavity 5.

[0025] The width B of the edge parts 3 and 4 is deliberately selected to be 2 mm, so that the connection in the edge parts 3 and 4 gives the entire safety belt 1 a flat shape. This effect can be further enhanced by selecting the width of the edge parts 3 and 4 to be larger, for example, the width B is 4 mm or more. This prevents the safety belt 1 from twisting or deforming around its longitudinal axis under the action of lateral forces when the edges of the edge parts 3 and 4 are unfolded. As long as it is within a reasonable range, the edge parts 3 and 4 can also be designed to be larger in width B, but this reduces the size of the cavity 5. For example, if the cavity 5 is deliberately implemented narrower in the form of a channel, whereby the arrangement and route of the lines in the safety belt 1 can be predetermined or defined, then this can be reasonable.

[0026] Figure 2a , Figure 2b and Figure 2c The seat belt dimensions for various hollow portions 14 are shown in FIG. The overall length L0 of the seat belt for a typical three-point seat belt arrangement for a motor vehicle is usually 3500 mm. The width A of the entire seat belt 1 is preferably 46 mm to 48 mm. Figure 2a The total width C of the cavity 5 in the belt is preferably a maximum of 37 mm in order to keep sufficiently large edge areas 3, 4 free, which ensures the planar shape of the entire seat belt 1. Figure 2b The two cavities 5 extending in parallel in the middle also have widths C1 and C2 preferably ranging from 10 mm to 18.5 mm, respectively, and Figure 2c The three cavities 5 extending in parallel in the belt 1 have a width C1, C2, C3 of preferably 10 mm to 12 mm, respectively. The length L1 of the hollow portion 14 or the cavity 5 shown is preferably 1300 mm to 1700 mm. However, only one hollow portion 14 is shown in each case. However, more hollow portions 14 interrupted by single-layer portions 15 can be provided along the entire length L0 of the safety belt 1. Therefore, in particular in the case of a three-point safety belt geometry, it is conceivable that when the safety belt is worn, the hollow portions 14 are only provided in the chest area and the hip area, but not in the area of ​​the movable belt tongue (when the belt tongue is anchored in the belt buckle), in particular not in the area of ​​the belt retractor and the restraint device. In these areas, it is more advantageous to arrange the single-layer portion 15. It is also advantageous if the hollow portion 14 or the hollow portion is designed and arranged so that the safety belt 1 is formed as a single-layer portion 15 in the area where it passes through the deflector fixed to the vehicle. The advantage of such a solution can be seen from the fact that the probability of the seat belt 1 twisting in the region of the movable belt tongue or in the region of the passage through the deflector fixed to the vehicle can be reduced. In principle, due to the hollow section 14, there is a risk that the two fabric layers will separate from each other and thus deform under the effect of shear forces or transverse forces. In the proposed region, this effect can be reduced by forming the seat belt 1 in particular as a single-layer section 15. The proposed region is therefore preferably selected because the probability of transverse forces occurring here is particularly high (deflector, belt tongue) or twisting is particularly unfavorable (belt retractor, deflector and belt tongue).

[0027] exist Figure 3 The safety belt 1 can be seen in the cross-section of . The two fabric layers 6 and 7 are woven in a 7 / 1 weave. The switching of the warp threads 11 from one side to the other of the shed in the loom of the fabric layer 6 or 7 is selected so that they are first arranged in a periodic sequence on one side of the shed, while seven weft threads 10 are ejected through the shed. The warp threads 11 are then switched to the other side of the shed for the weft threads to eject the next weft thread 10, and then switched back to the other side of the shed to repeat the weaving rhythm of the subsequent seven weft threads 10 of the next cycle. This results in a rhythm in which seven respective weft threads 10 cover the warp threads 11 towards one side, and then one weft thread 10 covers the warp threads 11 on the other side, after which the rhythm is repeated. The warp threads 11 of the fabric layers 6 and 7 are woven in bundles (multifilaments) or individually as monofilaments. Thus, a first bundle of warp threads 11 is woven with the described rhythm, while an adjacent second bundle of warp threads 11 is woven with the same but offset rhythm. As Figure 3As shown, the warp threads 11 of the two different fabric layers 6 and 7 are further woven with the same described weaving rhythm, but offset relative to each other.

[0028] As an alternative to the described 7 / 1 weave, a 5 / 1 / 1 weave or a 3 / 1 weave or a 5 / 1 / 1 / 1 weave is also conceivable, wherein in principle weft threads 10 with a yarn count of 100 to 1100 dtex can be used as monofilaments or multifilaments.

[0029] The two fabric layers 6 and 7 woven separately from each other in this way are connected to each other by at least one edge weaving thread 12 in the edge portion 3 shown. The edge weaving thread 12 is woven with the weft threads 10 of the two fabric layers 6 and 7 in a 4 / 4 weave, that is, the edge weaving thread 12 is guided on one side of the shed of one of the fabric layers 6 or 7 for the four weft threads 10 of the two fabric layers 6 and 7, and then switched to the opposite side of the shed of the other fabric layer 6 or 7.

[0030] Thus, in the finished woven safety belt 1, the edge braiding wire 12 extends periodically for four weft threads 10 on the lower side of the lower fabric layer 6 in the illustration and for the next four weft threads 10 on the upper side of the upper fabric layer 7 shown in the illustration. Therefore, it extends periodically on the two free surfaces of the fabric layers 6 and 7, and thus switches sides because it passes through the weft threads 10 of the two fabric layers 6 and 7 to reach the other free surface. The edge braiding wire 12 thus extends continuously in the single-layer portion 15, in which the two fabric layers 6 and 7 are connected over the entire surface of the safety belt to form a single integral fabric layer, and in the hollow portion 14, a cavity 5 is provided. The edge braiding wire 12 can also be woven as a multifilament bundle, wherein multiple bundles or individual edge braiding wires 12 can also be provided, which can be woven offset relative to each other. This is particularly reasonable for realizing the width B of the edge portions 3 and 4, so as to simultaneously realize the corresponding plane shapes of the edge portions 3 and 4 with the width B.

[0031] exist Figure 3 Also visible in the figure are the central weaving threads 13, which in the single-layer section 15 shown in the left area connect the two fabric layers 6 and 7 to each other in a 2 / 1 / 1 / 1 / 2 weave. The central weaving threads 13 thus extend periodically, initially alternating over the two free surfaces of the fabric layers 6 and 7, respectively, and thus switching sides, as they pass through the weft threads 10 of the two fabric layers 6 and 7 to the other free surface. At the transition from the single-layer section 15 to the hollow section 14 shown on the right, the periodic weaving pattern of the central weaving threads 13 is interrupted and transitions discontinuously to a new periodic weaving pattern, which is now woven only in one fabric layer 6 or 7 and preferably corresponds to the periodic weave of the warp threads 11; in the embodiment shown, this periodic weave is a 7 / 1 weave.

[0032] In principle, the braiding threads 12, 13 can differ from the warp threads 11 in material, yarn thickness, color, elongation and various other properties, since in principle they have a different task than the warp threads 11 to achieve the connection. For example, the braiding threads 12, 13 do not need to absorb any tension under load, so that they can be formed from yarns with a lower yarn thickness than the warp threads 11.

[0033] exist Figure 3 In the illustration of FIG. 1 , the fabric layers 6 and 7 have been pulled apart in the course of the warp threads 11, the weft threads 10 and the braiding threads 12, 13, wherein the weft threads 10 of the two fabric layers 6 and 7 are arranged in one plane, respectively, so that the weaving pattern is more obvious. However, in the finished safety belt 1, the warp threads 11, the weft threads 10 and the braiding threads 12, 13 are significantly more closely present together in the flat braid, wherein about 10 to 15 weft threads can be provided per centimeter length of the safety belt 1.

Claims

1. A seat belt (1) for a seat belt device of a motor vehicle, comprising - at least one hollow part (14) having at least one cavity (5) for accommodating electronic components and / or circuits, wherein - the cavity (5) is formed by two fabric layers (6, 7), - the fabric layer (6, 7) is formed by a plurality of warp threads (11) and weft threads (10), - the fabric layers (6, 7) are connected to each other in the outer edge portions (3, 4) by one or more edge braiding threads (12) extending parallel to the longitudinal direction of the safety belt (1), wherein - at least one single-layer portion (15) adjoins the at least one hollow portion (14) in the longitudinal direction of the safety belt (1), wherein the single-layer portion (15) is formed by the two fabric layers (6, 7), wherein - the fabric layers (6, 7) in the central portion (2) between the edge portions (3, 4) are interconnected by a plurality of central braided threads (13) extending parallel to the longitudinal direction of the safety belt (1), and wherein - The central braiding thread (13) in the hollow portion (14) is braided together only in one of the fabric layers (6, 7).

2. The safety belt (1) according to claim 1, characterized in that - The safety belt (1) has a width (A) of 40 mm to 50 mm, and the fabric layers (6, 7) are connected to each other in the edge parts (3, 4) by the edge braiding thread (12), and the edge parts (3, 4) each have a width (B) of at least 2 mm.

3. The safety belt (1) according to claim 2, characterized in that - the hollow portion (14) has a length of 1300 mm to 1700 mm, and the cavity (5) arranged in the hollow portion (14) has a width (C) of 10 mm to 37 mm.

4. A safety belt (1) according to any one of the preceding claims, characterised in that A portion of the seat belt (1) is a single-layer portion (15) which, when worn, is arranged in the area of ​​a deflector or a seat belt tongue in a seat belt device of a motor vehicle or is wound around a seat belt retractor after unbuckling.

5. The safety belt (1) according to claim 1, characterized in that - In the hollow portion (14), the central weaving thread (13) in one of the fabric layers (6, 7) is woven in the same weave as the warp threads (11) belonging to the fabric layer.

6. The safety belt (1) according to claim 1, characterized in that - The warp threads (11) are connected to the weft threads (10) in a 7 / 1 weave.

7. The safety belt (1) according to claim 1, characterized in that - The two fabric layers (6, 7) are connected to each other in one or more hollow parts (14) to form two or more cavities (5) separated from each other.

8. The safety belt (1) according to claim 1, characterized in that - At least one electrical line and / or one electronic component is arranged in the cavity (5).

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