CN113859168B

CN113859168B - Automotive interior part substrate, preparation method of substrate and automotive interior part

Info

Publication number: CN113859168B
Application number: CN202111156183.2A
Authority: CN
Inventors: 杨杉苗; 赵铮; 朱波; 王有坤
Original assignee: Ningbo Tuopu Group Co Ltd
Current assignee: Ningbo Tuopu Group Co Ltd
Priority date: 2021-09-30
Filing date: 2021-09-30
Publication date: 2022-11-25
Anticipated expiration: 2041-09-30
Also published as: WO2023051841A1; CN113859168A

Abstract

The invention provides an automobile interior part substrate, a preparation method of the substrate and an automobile interior part. Compared with the prior art, the invention directly fixes the stress line on the substrate body, has better effect of fixing the air bag door, simpler production process, can improve the production efficiency and reduce the production cost, and has very high economic value and popularization prospect.

Description

Automotive interior part substrate, preparation method of substrate and automotive interior part

Technical Field

The invention relates to the technical field of automobile accessories, in particular to an automobile interior trim part substrate, a preparation method of the substrate and an automobile interior trim part.

Background

In order to improve the safety of the vehicle, safety airbags are arranged at the parts of a steering wheel, an instrument panel, a vehicle door and the like of the vehicle, the safety airbags are arranged in the interior trim parts of the vehicle and are shielded by airbag doors, and the airbag doors can be opened and turned around a rotating shaft in the explosion process of the airbags. In the prior art, a mesh cloth is arranged at a rotating shaft part of an air bag door, a fixing part is arranged on a substrate of an automotive interior part, and the mesh cloth is fixed on the fixing part. When the air bag door is opened, the grid cloth can tightly fix the air bag door and the automotive interior trim part by using the strength of the grid cloth, so that the air bag door is prevented from being torn and flying out.

However, the fixing structure adopting the mesh cloth has some defects, and the mesh cloth needs to bear large tearing force when the air bag door is opened, so that the requirements on the performances of the mesh cloth, such as extension, fracture and the like, are extremely high, the mesh cloth needs to be woven by adopting a special process, and the mesh cloth also needs to be treated by a special compression process, so that the manufacturing cost is high, and the production cost is high; in addition, the material of the base plate of the automotive interior part is limited, the non-pure injection molding part is difficult to fix the mesh cloth, the base plate is provided with the fixing part and needs to be molded through a double-material injection molding process, and the process needs two molds for injection molding twice, so that the production efficiency is reduced, and the equipment cost is increased.

Disclosure of Invention

The invention aims to provide a novel air bag door anti-tearing structure, and aims to solve the technical problems of reducing the tearing and flying-out risk of an air bag door and reducing the manufacturing cost of an automotive interior trim part.

In order to solve the above problems, a first aspect of the present invention provides an automotive interior substrate, including a substrate body and a stress line fixed on the substrate body, where the stress line is connected to the substrate body by sewing, the substrate body includes an airbag door, a weakening groove is provided on the substrate body, an extension line of the weakening groove forms an edge of the airbag door, a connection line between two ends of the weakening groove forms a rotation shaft of the airbag door, and a position where the stress line is disposed corresponds to the rotation shaft.

Compared with the prior art in which an independent grid cloth is arranged to fix the airbag door, the stress line is directly fixed on the substrate body, the effect of fixing the airbag door is better, the production process is simpler, the production efficiency can be improved, the production cost is reduced, and the airbag door has high economic value and popularization prospect.

In a preferred or alternative embodiment, the force-receiving line includes a plurality of stretching portions and a plurality of bending portions, each stretching portion is connected to each other by the bending portions, each stretching portion passes through the rotating shaft, and each bending portion is disposed on both sides of the rotating shaft. Thus, the plurality of stretching portions can share the explosive force when the airbag is opened, the requirement for the performance of the stress line itself is reduced, and the bending portion can increase the frictional force between the stress line and the substrate body, and share the force applied to the stretching portions by the portions.

In a preferred or alternative embodiment, the stretch is linear. Thereby, the stretching portion can exert the maximum performance, and the stretching portion arrangement is facilitated.

In a preferred or alternative embodiment, the stretching portions are parallel to each other. Therefore, the stress is uniformly distributed among all the stretching parts, and the integral bearing capacity of the stress line is improved.

In a preferred or alternative embodiment, the spacing between the stretching portions is equal. Therefore, the stretching parts are uniformly arranged, and the stress among the stretching parts is more uniform.

In a preferred or alternative embodiment, the angle between the stretching section and the rotation axis is α,90 ° ≧ α > 0 °. Therefore, the included angle between the stretching part and the rotating shaft is limited, and the stretching part can exert the stretching performance when the rotating shaft is torn.

In a preferred or alternative embodiment, the angle between the stretching part and the rotation axis is α,90 ° ≧ α ≧ 60 °. Therefore, the included angle between the stretching part and the rotating shaft is further limited, so that the stretching part can better exert the stretching performance.

In a preferred or alternative embodiment, the lengths of the respective stretching portions are equal. Therefore, the uniform stress of each stretching part is facilitated, and the stress lines are convenient to arrange.

In a preferred or alternative embodiment, the length of the stretch is L _s ，100mm≥2L _s* sin alpha is more than or equal to 1mm. Therefore, the length of the stretching part is limited, and each stretching part can bear certain tensile force.

In a preferred or alternative embodiment, the length of the shaft is L _y The number of the stretching parts is X, and the length of 10cm is more than or equal to L _y the/X is more than or equal to 0.5cm. Therefore, the number of the stretching parts is limited, and the impact resistance of the whole stress line is ensured.

In a preferred or alternative embodiment, the elongation of the stress line is between 10% and 100%. Therefore, the performance of the stress line is limited, and the whole impact bearing capacity of the stress line is ensured.

In a preferred or alternative embodiment, the force line has a breaking strength of 500 to 50000N/cm. Therefore, the performance of the stress line is limited, and the whole impact bearing capacity of the stress line is ensured.

In a preferred or alternative embodiment, the bend is U-shaped, V-shaped or ] shaped. Therefore, the bending part can increase the friction force between the stress line and the substrate body, and the stress line is convenient to arrange.

In a preferred or alternative embodiment, the ratio of the sum of the lengths of the stretching parts to the sum of the lengths of the bending parts is 1. Therefore, the lengths and the proportions of the stretching part and the bending part can be designed according to the tensile force to be borne, so that the total explosive force borne by the stress line can be adjusted.

In a preferred or optional embodiment, the force-bearing line comprises connecting parts arranged at two ends, and the connecting parts are connected with the substrate body in a sewing mode. Therefore, the two ends of the stress line are sewn on the substrate body, the connection is reliable, and the processing is convenient.

In a preferred or alternative embodiment, the shape of the connecting portion is a dogleg shape. Therefore, the large-amplitude displacement of the stress line is restricted, and the two ends of the stress line are prevented from being separated from the substrate body.

In a preferred or alternative embodiment, the angle between adjacent fold lines in said connecting portion is between 1 ° and 89 °. Therefore, the connection reliability of the connecting part is further improved, and the connecting part is prevented from being separated from the substrate body.

In a preferred or alternative embodiment, the density of stitches stitched through the connecting portion is 1-10 stitches/cm ² . Therefore, the connection reliability of the connecting part and the substrate body is ensured.

In a preferred or alternative embodiment, the force-bearing threads are woven from yarns of one or more materials. Therefore, the stress line has no special requirements on materials, and the production cost is low.

In a preferred or alternative embodiment, the force-bearing thread is braided from one or more yarns. Therefore, the stressed wire can adjust the performance by increasing the number of yarns without adopting special processes or materials, and the production cost is lower.

In a preferred or alternative embodiment, the substrate further comprises a fixing line, wherein the fixing line is connected with the substrate body and fixes the stress line on the substrate body. Therefore, the stress line is fixed on the substrate body by the fixing line, the processing is simple and convenient, the fixing is reliable, and the stress line cannot be separated from the substrate body.

In a preferred or alternative embodiment, the fixing line is a zigzag line, the fixing line includes fixing portions and turning portions, the fixing portions are connected by the turning portions, the turning portions are distributed on two sides of the force-bearing line, and the fixing portions press the force-bearing line. Therefore, the stress line can obtain larger friction force under the extrusion of the fixing line during blasting, the tensile force applied to the stress line by the part is shared, and the stress can be shared among the fixing parts.

In a preferred or alternative embodiment, the total length of the force line is L _x The number of the fixing parts is Y, and then 10mm is more than or equal to L _x the/Y is more than or equal to 0.5mm. Therefore, the number of the fixing parts can be adjusted according to the impact force required to be born, and the fixing parts are prevented from being broken.

In a preferred or alternative embodiment, the included angle between adjacent fixing portions is between 1 ° and 89 °. Therefore, the fixing effect of the fixing part is improved, and the stress line is prevented from being separated from the substrate body.

In a preferred or alternative embodiment, the included angle between each adjacent fixing portion is equal. Therefore, the stress can be evenly distributed among the fixing parts.

In a preferred or alternative embodiment, each of the inflections is stitched to the substrate body. Therefore, the fixing lines are sewn on the substrate body at multiple points, the connection is reliable, and the processing is convenient.

In a preferred or alternative embodiment, the density of stitches of the turn stitching is 1-10/cm ² . Therefore, the fixing line is reliably connected with the substrate body and cannot be separated from the substrate body.

In a preferred or alternative embodiment, the securing thread is woven from yarns of one or more materials. Therefore, the fixed wire has no special requirements on materials and is low in production cost.

In a preferred or alternative embodiment, the securing thread is woven from one or more yarns. Therefore, the performance of the fixed line can be adjusted by increasing the number of yarns, special processes or materials are not needed, and the production cost is low.

In a preferred or alternative embodiment, the base plate body is made of a fiberboard material. Therefore, the stress line can be sewn on the substrate body, the substrate body does not need to be formed through a double-material injection molding process, and the production cost is reduced.

The second aspect of the present invention provides a method for preparing a substrate for an automotive interior part, comprising the steps of: positioning a substrate body, forming a weakening groove on the substrate body, wherein the weakening groove forms the edge of an air bag door, and a connecting line between two ends of the weakening groove forms a rotating shaft of the air bag door; sewing a stress line on the substrate body, wherein the stress line corresponds to the rotating shaft; and moving the substrate body to a hot press for hot press molding to obtain the automotive upholstery substrate.

Compared with the prior art, the preparation method has the advantages of few process steps, simple production method, improved production efficiency and reduced production cost.

The third aspect of the invention provides an automotive interior, which comprises the automotive interior substrate.

Compared with the prior art, the automobile interior part adopts the base plate with a brand new structure, the air bag door is fixed by the stress lines, and the grid cloth processed by a special process is not needed, so that the preparation cost can be reduced, and the production efficiency can be improved.

Drawings

FIG. 1 is a cross-sectional view of an automotive interior trim component in accordance with an embodiment of the present invention;

FIG. 2 is an enlarged view of a portion of FIG. 1 at A;

FIG. 3 is a rear view of an automotive interior trim component according to an embodiment of the present invention;

FIG. 4 is a diagram illustrating a substrate according to an embodiment of the present invention;

FIG. 5 is a layout view of the force lines and the holding lines on the substrate body according to an embodiment of the present invention;

FIG. 6 is a dimension plot of the force line and the fixation line in an embodiment of the present invention.

Description of reference numerals:

1-substrate body, 11-air bag door, 12-weakening groove, 13-rotating shaft, 14-sewing line area, 2-stress line, 21-stretching part, 22-bending part, 23-connecting part, 3-fixing line, 31-fixing part, 32-bending part, 4-surface skin and 5-air bag frame.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, it need not be further defined or explained in subsequent figures.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "disposed," "connected," and the like are to be construed broadly, such as "connected," which may be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it should be understood that they are presented herein only to illustrate and explain the present invention and not to limit the present invention.

Referring to fig. 1 to 4, an embodiment of the present invention provides an automotive interior, which includes a skin 4, a substrate, and an airbag frame 5, which are sequentially disposed, wherein the skin 4 is attached to a surface of the substrate, the airbag frame 5 is disposed on a back surface of the substrate, and an airbag of an automobile is adapted to be disposed in the airbag frame 5. The base plate comprises a base plate body 1, the base plate body 1 comprises an airbag door 11, a concave weakening groove 12 is formed in the base plate body 1, the weakening groove 12 forms the edge of the airbag door 11, and a connecting line between two ends of the weakening groove 12 forms a rotating shaft 13 of the airbag door 11, as shown by a chain line in fig. 3. When the safety airbag is opened, a bursting force is generated, the airbag door 11 is torn along the weakening groove 12 and overturned along the rotating shaft 13, and the rotating shaft 13 of the airbag door 11 can be torn due to the fact that the bursting force is large.

The base plate of the embodiment comprises a stress line 2, a seam area 14 is defined at the corresponding part of the rotating shaft 13, namely the part surrounded by a dotted line in fig. 3, and the stress line 2 is arranged in the seam area 14 and is connected with the base plate body 1 in a sewing way. When the rotating shaft 13 is torn, the stress line 2 can pull the air bag door 11, the air bag door 11 is prevented from being completely separated from the substrate body 1, the air bag door 11 is prevented from flying out to damage people in the vehicle, and safety is improved.

This embodiment with 2 snap-fits of stress line on base plate body 1, compare with the structure that prior art set up net cloth alone, fixed gasbag door 11 effect is better, and production technology is simpler, can improve production efficiency, reduction in production cost has very high economic value.

In this embodiment, the substrate body 1 is made of NFPP plate, and in other embodiments, the substrate body 1 may be made of fiber board made of other materials, such as PPGF. Compare in the injection molding, the fibreboard is more environmental protection durable, and the stress line 2 of also being convenient for is sewed up with base plate body 1 and is connected. Meanwhile, the substrate body 1 does not need to be formed by a double-material injection molding process like the prior art, so that the use of production equipment can be reduced, and the production cost is reduced.

As shown in fig. 5 and 6, the force receiving wire 2 includes a plurality of stretching portions 21 and a plurality of bending portions 22, the stretching portions 21 are used for pulling the airbag door 11, and the stretching portions 21 pass through the rotating shaft 13; the bending portions 22 are used to connect the stretching portions 21, and the bending portions 22 are disposed on both sides of the rotating shaft 13. The plurality of stretching portions 21 can distribute the explosive force when the airbag is opened, and reduce the requirement for the performance of the force receiving wire 2 itself, and the bending portion 22 can increase the frictional force between the force receiving wire 2 and the substrate body 1 in addition to the function of connecting the stretching portions 21, and can distribute the force partially applied to the stretching portions 21. The both ends of atress line 2 with be equipped with connecting portion 23, connecting portion 23 and base plate body 1 are sewed up and are connected, sew up the both ends of atress line 2 on base plate body 1, connect reliably, processing is convenient.

Furthermore, the shapes of all parts of the stress line 2 are limited, so that the impact resistance and the connection reliability of the stress line can be improved. In the present embodiment, stretching portion 21 is linear, whereby stretching portion 21 can exert the maximum performance and arrangement of stretching portion 21 is facilitated. The bent portion 22 is U-shaped, and the U-shaped bent portion 22 is easy to be disposed, and can make the friction between the stress line 2 and the substrate body 1 larger. In other embodiments, the bent portion 22 may also be V-shaped or ] shaped. The connecting portion 23 is formed in a zigzag shape, and can restrict a large displacement of the stress line 2 and prevent both ends of the stress line 2 from being separated from the substrate body 1.

Further, the force receiving wire 2 mainly holds the airbag door 11 by the stretching portion 21, and the design of the structure of the stretching portion 21 can distribute the force received by each stretching portion 21, thereby improving the receiving ability and preventing the breakage of the stretching portion 21. In this embodiment, the stretching portions 21 are parallel to each other, the intervals between the stretching portions 21 are equal, and the lengths of the stretching portions 21 are equal, which is beneficial to evenly distribute the stress among the stretching portions 21 and improve the overall bearing capacity of the stress line 2.

In this embodiment, the length L of the rotating shaft 13 _y 25cm, the number X of stretching parts 21 is 20, L _y and/X =1.25cm. In other embodiments, the number of extensions 21 is limited to 10cm ≧ L _y X is more than or equal to 0.5cm, and is controlled byThe number of the stretching portions 21 can adjust the impact resistance of the whole stress-bearing wire 2, thereby ensuring the safety of the automotive interior.

In the present embodiment, the angle α between the stretching portion 21 and the rotation axis 13 is 90 °, and in other embodiments, 90 ° ≧ α > 0 °, preferably 90 ° ≧ α > 60 °. The included angle between the stretching part 21 and the rotating shaft 13 is limited, so that the stretching part 21 can exert the stretching performance when the rotating shaft 13 is torn, and the stress is maximum in the vertical direction of the rotating shaft 13 under normal conditions, therefore, when the alpha is more than or equal to 90 degrees and more than or equal to 60 degrees, the stress line 2 can exert the performance better.

In the present embodiment, the length of the stretching part 21 is L _s 60mm, and the extension length of the stretching part 21 in the direction perpendicular to the rotating shaft 13 is 2L _s * sin α =60mm. In other embodiments, the extension length of the stretching portion 21 in the vertical direction of the rotating shaft 13 is limited, 100mm ≧ 2ls sin α ≧ 1mm, so as to ensure the stretching effect and avoid the stretching tearing, and preferably 70mm ≧ 2ls sin α ≧ 30mm, further improve the stretching ability.

In the present embodiment, the ratio of the length of each stretching portion 21 to the sum of the lengths of the bent portions 22 is 5. The length and the proportion of the stretching part 21 and the bending part 22 can be designed according to the tensile force to be borne, so as to adjust the total explosive force which can be borne by the stress wire 2.

Since the stress is uniformly distributed among the stretching portions 21 of the stress line 2 in this embodiment, the overall bearing capacity is greatly improved, and the performance requirement on the stress line 2 itself is reduced. The stress line 2 can be formed by weaving yarns made of one or more materials, such as aramid yarns, PET (polyethylene terephthalate) yarns, PP (polypropylene) yarns and the like, and compared with the existing mesh cloth, the material cost is greatly reduced. The stress line 2 can also be woven by one or more yarns, the performance can be adjusted by increasing the number of the yarns without adopting special processes or materials, and the production cost is lower.

Furthermore, the performance of the stress line 2 is limited, the elongation is 10% -100%, the breaking strength of the stress line 2 is 500-50000N/cm, and the whole impact resistance of the stress line 2 is ensured.

In this embodiment, the connection portion 23 is a fold line, the included angle between adjacent fold lines in the connection portion 23 is β 45 °, in other embodiments, β is greater than or equal to 89 ° or equal to 1 °, preferably greater than or equal to 45 ° or equal to 15 °, and β is adjusted to improve the connection reliability of the connection portion 23 and prevent the connection portion from being separated from the substrate body 1.

Furthermore, the density of stitches sewn on the connecting part 23 is 1-10/cm ² The stitch density can be adjusted according to the force required to bear, and the connection between the connecting part 23 and the substrate body 1 is ensured to be reliable.

As shown in fig. 5 and 6, the substrate body 1 is further provided with a fixing line 3, which is connected to the substrate body 1 by sewing, and the fixing line 3 is disposed along the extending direction of the stress line 2 and is used for fixing the stress line 2 on the substrate body 1. In the embodiment, the stress line 2 is fixed on the substrate body 1 through the fixing line 3, the processing is simple and convenient, the fixing is reliable, and the stress line 2 cannot be separated from the substrate body 1.

The fixing line 3 is a fold line, and comprises fixing portions 31 and turning portions 32, wherein the fixing portions 31 are connected by the turning portions 32, the turning portions 32 are distributed on two sides of the stress line 2, and the fixing portions 31 press the stress line 2. The turning part 32 is connected with the base plate body 1 in a sewing way, so that the fixing line 3 is sewn on the base plate body 1 at multiple points, the connection is reliable, and the processing is convenient.

Further, the stitch density of the stitch defining the turn 32 is 1-10 stitches/cm ² And the fixing line 3 is reliably connected with the substrate body 1 and cannot be separated.

When the safety airbag is exploded, the stress line 2 can obtain larger friction force under the extrusion of the fixing line 3, the split part applies the pulling force on the stress line 2, and the stress can be split among the fixing parts 31 to prevent the fixing line 3 from being broken.

In this embodiment, the fixing portions 31 share the stress with each other, so that the requirement on the performance of the fixing thread 3 is reduced, and the fixing thread can be woven by yarns made of one or more materials, and the production cost is low. The yarn can also be woven by one or more yarns, the performance is adjusted by increasing the number of the yarns, special processes or materials are not needed, and the production cost is low.

Further, the structure of the fixing wire 3 is limited, so that the stress capacity of the fixing wire can be improved. The included angle γ between adjacent fixing portions 31 is equal, and γ is 45 ° in this embodiment. In other embodiments, 89 ° ≧ γ ≧ 1 °, preferably 45 ° ≧ γ ≧ 15 °, the fixing effect of the fixing portion 31 can be improved by adjusting the included angle of the adjacent fixing portion 31, and the force-bearing line 2 is prevented from being detached from the substrate body 1.

In the present embodiment, the total length L of the force-receiving wire 2 _x 1152mm, the number of fixing portions 31 is 160, L _x Y =7.2mm. In other embodiments, 10mm ≧ L is defined _x the/Y is more than or equal to 0.5mm, the number of the fixing parts 31 can be adjusted according to the impact force required to be born, and the fixing parts 31 can not be broken.

Another embodiment of the present invention provides a method for manufacturing a substrate for an automotive interior, including the steps of:

s1, positioning a substrate body 1, forming a weakening groove 12 in the substrate body 1, wherein the weakening groove 12 forms the edge of an airbag door 11, and a connecting line between two ends of the weakening groove 12 forms a rotating shaft 13 of the airbag door 11;

s2, sewing the stress line 2 on the substrate body 1, wherein the stress line 2 corresponds to the rotating shaft 13 and is positioned in the sewing area 14;

and S3, moving the substrate body 1 to a hot press for hot press molding to obtain the substrate of the automotive interior trim part.

The preparation method of the embodiment has the advantages of few process steps, simple production method, capability of improving the production efficiency, reduction of the use of production equipment and reduction of the production cost, and very high economic value.

Further, in the step S2, the arrangement structure of the stress lines 2 and the layout structure of the stress in the above embodiment are referred to, and the step S2 further includes sewing and fixing lines 3, so as to fix the stress lines 2 on the substrate body 1, and ensure that the stress lines 2 can bear the impact force generated during the explosion of the airbag.

Finally, it should be noted that the above embodiments are only used for illustrating the technical solutions of the present invention, and not for limiting the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The base plate is characterized by comprising a base plate body (1) and stress lines (2) fixed to the base plate body (1), wherein the stress lines (2) are connected with the base plate body (1) in a sewing mode, the base plate body (1) comprises an air bag door (11), a weakening groove (12) is formed in the base plate body (1), extending lines of the weakening groove (12) form the edge of the air bag door (11), connecting lines between two ends of the weakening groove (12) form a rotating shaft (13) of the air bag door (11), the stress lines (2) are arranged at positions corresponding to the rotating shaft (13), the stress lines (2) are formed by weaving yarns made of one or more materials, each stress line (2) comprises a plurality of stretching portions (21) and a plurality of bending portions (22), each stretching portion (21) is connected with each other through the bending portions (22), and each stretching portion (21) penetrates through the rotating shaft (13), and each bending portion (22) is arranged on two sides of the rotating shaft (13).

2. The automotive upholstery substrate according to claim 1, wherein the stretch portion (21) is linear.

3. The automotive interior substrate according to claim 2, wherein the stretching portions (21) are parallel to each other.

4. The automotive interior substrate according to claim 3, wherein the stretched portions (21) are equally spaced from each other.

5. The automotive trim substrate according to claim 2, characterized in that the stretching portion (21) and the rotation axis (13) form an angle α, wherein 90 ° ≧ α > 0 °.

6. The automotive trim substrate according to claim 5, characterized in that the stretching portion (21) and the rotation axis (13) form an angle α, wherein 90 ° ≧ α ≧ 60 °.

7. The automotive interior substrate according to claim 5, characterized in that the lengths of the stretching portions (21) are equal.

8. The automotive interior substrate according to claim 7, wherein the length of the stretching portion (21) is Ls,100mm ≧ 2L _s *sinα≥1mm。

9. The automotive trim substrate according to claim 1, characterized in that the length of the rotating shaft (13) is L _y The number of the stretching parts (21) is X, and 10cm is more than or equal to L _y /X≥0.5cm。

10. The automotive trim substrate according to any one of claims 1 to 9, characterized in that the elongation of the force-bearing thread (2) is 10% to 100%.

11. The automotive trim substrate according to any one of claims 1 to 9, characterized in that the force line (2) has a breaking strength of 500 to 50000N/cm.

12. The automotive trim substrate according to claim 1, characterized in that the bend (22) is U-shaped, V-shaped or ] shaped.

13. The automotive interior substrate according to claim 1, wherein a ratio of a sum of lengths of the stretched portions (21) to a sum of lengths of the folded portions (22) is 1.

14. The automotive trim substrate according to claim 1, characterized in that the force-bearing wire (2) comprises connecting parts (23) arranged at both ends, and the connecting parts (23) are connected with the substrate body (1) in a sewing manner.

15. The automotive interior substrate according to claim 14, wherein the connecting portion (23) has a zigzag shape.

16. The automotive trim substrate according to claim 15, characterized in that the angle between adjacent folding lines in the connecting portion (23) is 1 ° to 89 °.

17. The automotive trim substrate according to claim 14, characterized in that the connecting portion (23) is stitched with a stitch density of 1-10 stitches/cm ² 。

18. The automotive interior substrate according to claim 1, characterized in that the force-bearing thread (2) is woven from one or more yarns.

19. The automotive interior substrate according to claim 1, further comprising a fixing wire (3), wherein the fixing wire (3) is connected to the substrate body (1) and fixes the force-bearing wire (2) to the substrate body (1).

20. The automotive trim substrate according to claim 19, wherein the fixing line (3) is a zigzag line, the fixing line (3) comprises fixing portions (31) and bent portions (32), the fixing portions (31) are connected by the bent portions (32), the bent portions (32) are distributed on two sides of the stress line (2), and the fixing portions (31) press the stress line (2).

21. Automotive upholstery substrate according to claim 20, wherein the force line (2) has a total length L _x The number of the fixing parts (31) is Y, and then 10mm is more than or equal to L _x /Y≥0.5mm。

22. The automotive trim substrate according to claim 20, characterized in that the included angle between adjacent anchor portions (31) is 1 ° to 89 °.

23. The automotive trim substrate according to claim 22, characterized in that the included angle between each adjacent fixing portion (31) is equal.

24. The automotive trim substrate according to claim 20, characterized in that each turn (32) is sewn to the substrate body (1).

25. The automotive trim substrate of claim 24, wherein the hinge (32) is stitched with a stitch density of 1-10 stitches/cm ² 。

26. Automotive upholstery substrate according to any one of the claims 19-25, wherein said fixing threads (3) are woven from one or more material yarns.

27. The automotive trim substrate according to any one of claims 19 to 25, characterized in that the fixing thread (3) is woven from one or more yarns.

28. The automotive trim substrate according to claim 1, characterized in that the substrate body (1) is made of a fiberboard material.

29. A method for preparing a substrate for automotive upholsteries according to any one of claims 1 to 28, comprising the steps of: positioning a substrate body (1), forming a weakening groove (12) on the substrate body (1), wherein the weakening groove (12) forms the edge of an airbag door (11), and a connecting line between two ends of the weakening groove (12) forms a rotating shaft (13) of the airbag door (11); sewing a stress line (2) on the substrate body (1), wherein the position of the stress line (2) corresponds to the rotating shaft (13); and moving the substrate body (1) to a hot press for hot press molding to obtain the substrate of the automotive interior trim part.

30. An automotive interior comprising the automotive interior substrate according to any one of claims 1 to 28.