Side part of rear part of motor vehicle body

Abstract

The invention relates to a rear side part (1) of a motor vehicle body, comprising a C-pillar (2), a D-pillar (3) and a wheel housing section (4) which is produced as a one-piece sheet-metal molded component in a press stroke, the C-pillar (2) and the D-pillar (3) being C-shaped, U-shaped or hat-shaped in cross section, the side part (1) having adjacent regions, the C-pillar (2) and the D-pillar (3) being formed in a U-shaped, U-shaped or hat-shaped in cross section, the C-pillar (2) and the D-pillar (3) being formed in a U-shaped, U-shaped or hat-shaped in cross section, and the D-pillar (3) being formed in a U-shaped, U-shaped or hat-shaped in cross section. The adjacent regions have different tensile strengths and / or different wall thicknesses from each other.

Description

Technical Field

[0001] The invention relates to a side part for the rear part of a motor vehicle body. Background Art

[0002] In motor vehicles or automobiles, an engine is used to drive the motor vehicle or automobile. Here, it can be an internal combustion engine, but it can also be an electric drive.

[0003] It is also known in the prior art that such motor vehicles, also called automobiles, have a monocoque. Such monocoques are made of individual metal components, mostly steel components. Aluminum components can also be used. The individual parts of the monocoque, thus the A-pillars, B-pillars, C-pillars, longitudinal beams, crossbeams, hood bows or also wheel arches, are manufactured individually and then assembled, in particular joined to one another, very particularly preferably welded. The monocoque is thus constructed. The individual components are manufactured, in particular, as extruded components.

[0004] For example, DE 10 2020 119 869 A1 or DE 10 2011 089 436 A1 discloses a side wall for a motor vehicle which is produced as an extruded component. Summary of the invention

[0005] The object of the present invention is to provide, based on the prior art, the possibility of providing a body component which can be produced simply and cost-effectively in terms of production technology but which at the same time improves the crash behavior and thus the occupant protection as well as the rigidity.

[0006] Thus, a rear side part of a motor vehicle body is shown. The rear side part has a C-pillar, a D-pillar and a wheel arch section or wheel arch part. The side part is produced as a one-piece sheet metal molded component, in particular in one press stroke. The side part has adjacent areas with different tensile strengths and / or different wall thicknesses.

[0007] "One-piece" can be understood as a sheet metal forming component that is cut from a one-piece, uniform sheet metal blank and then formed in one press stroke. Alternatively, in the sense of the present invention, one-piece refers to a component blank that is manufactured before forming, in particular extrusion forming or deep drawing, for example as a tailored welded blank or a tailored rolled blank. According to the present invention, it is particularly provided that components that are large in their external dimensions are manufactured in one press stroke with an extrusion movement. Therefore, it is not necessary to manufacture individual components such as C-pillars, D-pillars and wheel arch sections and wheel arches, but rather the components are manufactured in one piece in one press stroke. As a result, the precision of the manufactured components is particularly improved. On the contrary, the manufacturing costs are reduced, thereby reducing the production costs.

[0008] The rear side part is in particular a steel component which is manufactured as a hot-formed and press-hardened component. As a result, different strength values ​​can be set with respect to the strength, in particular the tensile strength Rm. The strong region has a tensile strength Rm of more than 1000 MPa, the high-strength region has a tensile strength Rm of more than 1350 MPa. In the sense of the invention, the soft region is designed with a tensile strength of less than 1000 MPa, in particular less than 850 MPa, preferably 500 MPa to 850 MPa.

[0009] In the sense of the invention, reinforcing patches can also be applied locally. The reinforcing patches are preferably applied before shaping.

[0010] For the purpose of forming freedom, it is now provided that at least one column, thus the C-column and / or the D-column, is formed in a C-shaped, U-shaped or cap-shaped manner in cross section. The wheel arch section itself is a large-area sheet metal component and is contoured to form a curved free shape after the forming process. In the lower region with respect to the vertical direction of the motor vehicle, a wheel arch is preferably arranged on the wheel arch section. In the sense of the invention, the wheel arch section can also partially form the inner side wall of the motor vehicle body in the region of the wheel arch section that is located at the top with respect to the vertical direction of the motor vehicle, so that only a part of the wheel arch is formed in the lower region of the wheel arch section and the corresponding wheel arch section is formed in a manner that extends in a spherical orientation only in this lower region.

[0011] In particular, the wheel arch section has an L-shaped configuration in the cross section itself in the area of ​​the wheel arch, so that in particular the legs of the L are arranged protruding outwards in the installed state. In addition, it is particularly preferred that a higher tensile strength and / or an increased wall thickness is configured in the area of ​​the wheel arch compared to the remaining area of ​​the wheel arch section.

[0012] According to the invention, the region of the C-pillar is likewise designed with a higher strength and / or wall thickness, so that the tensile strength is greater than 980 MPa, in particular greater than 1000 MPa and particularly preferably greater than 1200 MPa.

[0013] The wheel arch itself is designed to be partially circular and extends over an angular range of more than 30 degrees, in particular more than 45 degrees, particularly preferably more than 60 degrees.

[0014] Furthermore, in the wheel arch section or at the wheel arch, the area located at the front with respect to the longitudinal direction of the vehicle can be designed such that a sill joint is provided, wherein the sill joint again has a higher tensile strength and / or wall thickness than the remaining area of ​​the wheel arch section. This increases the rigidity of the vehicle body, in particular during operation, but also in the event of a crash, for corresponding straight-ahead driving.

[0015] The sheet metal blanks to be prepared first and then processed are particularly preferably tailored blanks. The tailored blanks are particularly preferably produced by laser welding. The joining area between the C-pillar and the D-pillar or between the C-pillar and the wheel arch section or between the D-pillar and the wheel arch section is then designed as a butt connection and is preferably welded by means of laser welding.

[0016] Alternatively or additionally or in a hybrid form, the individual previously mentioned connection points, i.e. between the C-pillar and the D-pillar, between the C-pillar and the wheel arch section and between the D-pillar and the wheel arch section, can also be designed to overlap at least partially and be produced, for example, by means of spot welding. However, the common point is that the component blanks or sheet metal blanks produced in this way are designed in one piece and are placed together in a large forming press (so-called gigabit presses) and then the entire rear side part is formed in one press stroke. Therefore, it is not necessary to form the individual components and then join them together, but the entire assembly of the rear side part is formed in an extrusion die in one press stroke. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Other advantages, features, characteristics and aspects of the present invention are the subject of the following description. Preferred design variants are shown in schematic diagrams. These drawings help to simplify the understanding of the present invention. It is shown in them:

[0018] Figure 1 A first embodiment variant of the rear side part is shown in a partial cross-section.

[0019] Figure 2 Shown according to Figure 1 An alternative design variant of the invention in which the component blank has a butt weld seam,

[0020] Figure 3 Shows Figure 2 An alternative design variant of the invention is provided in which an overlapping region is provided on the component blank, and

[0021] Figure 4 A side view of an alternative design variant of the rear side part is shown.

[0022] Reference numerals list

[0023] 1 Rear side parts

[0024] 2 C-pillar

[0025] 3 D-column

[0026] 4 Wheel housing section

[0027] 5 Wheel arch

[0028] 6 Transition area between 2 and 5

[0029] 7 Transition area between 2 and 3

[0030] 8 Transition area between 3 and 5

[0031] 9 Transition area between 7 and 4

[0032] 10 Transition zone between 3 and 4

[0033] 11 Transition zone between 5 and 4

[0034] 12 Spot welding

[0035] 13 Threshold connection area

[0036] 14 Window Glass

[0037] 15 Threshold

[0038] x Longitudinal direction of the vehicle

[0039] y Transverse direction of the vehicle

[0040] z Vertical direction of the vehicle

[0041] α Angle

[0042] β angle DETAILED DESCRIPTION

[0043] Figure 1 The side wall 1 of a motor vehicle is shown in a corresponding partial sectional view. This side wall is the side wall 1 located at the rear with respect to the longitudinal direction x of the motor vehicle. The side wall 1 has a D-pillar 3 and a wheel arch section 4, which also has an upper roof frame area in a similar manner. The wheel arch section 4 has a wheel arch 5 in the lower area with respect to the vertical direction z of the motor vehicle. The entire component is produced in one piece from a sheet metal blank in a press in one press stroke. The individual partial cross-sectional views according to the section line AA show that the C-pillar 2 is shaped in a cap shape in its cross section itself, with a flange protruding from it. The partial cross-sectional view along the section line BB shows that the D-pillar 3 is configured in a C-shaped or U-shaped manner in its section. The cross-sectional view according to the section line CC shows that the wheel arch section 4 has a protruding leg in the lower area, so that the leg is L-shaped in the cross section, or is contoured in a spherical segment shape or as a curved free form by a slight curvature. The wheel arch 5 protrudes outward and thus provides a geometric reinforcement.

[0044] In relation to the angle α, the wheel arch 5 is preferably formed in a circumferential or circular segment-shaped manner, preferably greater than 30°, in particular greater than 45°, and preferably greater than 60°. The individual transition regions are preferably shown here on the component blank, which then causes the entire rear side part 1 to be formed into a tailored blank that is butted against each other and laser welded. In particular, the transition region 6 between the C-pillar 2 and the wheel arch 5 or the wheel housing section 4 is shown. In addition, the transition region 7 between the D-pillar 3 and the C-pillar 2 and the transition region 8 between the D-pillar 3 and the wheel arch 5 are shown. Similarly, a corresponding transition region 9 between the C-pillar 2 and the wheel housing section 4 and a transition region 10 between the wheel housing section 4 and the D-pillar 3 can be constructed. These transition regions can also be constructed as tailored welded blanks.

[0045] As a result, a greater wall thickness can be used in the C-pillar 2 or in the D-pillar 3 in relation to the wall thickness to be used than in the wheel arch section 4. The wheel arch 5 itself can also be placed again with the transition region 11 on the wheel arch section 4, in which case a blunt laser weld can also be formed over the entire length region of the transition region. Therefore, the wheel arch 5 can also have a greater wall thickness than the remaining wheel arch sections, but preferably a smaller wall thickness than the wall thickness of the C-pillar. By selecting different steel qualities with different hardenability and / or carrying out corresponding customized tempering before, during or after hot forming, the tensile strengths can also be different from each other accordingly. Particularly preferably, a greater wall thickness and / or a higher tensile strength is used in the upper region of the C-pillar 2 than in the lower region of the C-pillar and / or than in the wheel arch section. In the region of the D-pillar 3, the same or a smaller tensile strength or a lower tensile strength is selected for the same or a smaller wall thickness compared to the C-pillar 2. However, with respect to the wheel arch section 4, the D-pillar 3 itself is constructed with a greater wall thickness or a greater tensile strength. A similar situation applies to the wheel arch 5. The wheel arch can also be provided with a greater wall thickness and / or a greater tensile strength in the finished component than the remaining areas of the wheel arch section. It can be seen in particular in the transitional or connecting areas 9 and 10 that the C-pillar 2 and the D-pillar 3 each extend as far as possible in the vertical direction z of the vehicle over a large part and thus also form the side areas of the wheel arch section 4. In the sense of the invention, the C-pillar 2 and the D-pillar 3 are not only in the upper area, in which the window frame or the window glass 14 is inserted.

[0046] Figure 2 Shows Figure 1 An alternative design variant of the invention. Here, the wheel arch 5 is extended and Figure 1. Here, the extension of the wheel arch 5 is constructed in such a way that the door sill 15 of the schematic representation of the vehicle body can be coupled here, especially in the longitudinal direction x of the vehicle and the vertical direction z of the vehicle. In this embodiment, the upper area of ​​the C-pillar 2 is preferably also constructed to have a larger wall thickness, and the large area of ​​the wheel housing section 4 with the minimum wall thickness is constructed to have a larger wall thickness. The wheel arch 5 is constructed to have such a wall thickness, which is between the maximum wall thickness of the C-pillar and the wall thickness of the surface area of ​​the wheel housing section. Preferably, the wheel arch 5 and at least the upper area of ​​the C-pillar 2 are hardened. The D-pillar 3 has a smaller wall thickness than the C-pillar 2, but has a larger wall thickness than the wheel housing section 4. The corresponding hardening can be carried out by customized tempering, so that the tensile strength is matched during the hot forming hardening process or matched by the steel quality that can be hardened differently in the tailored welded blank. The hardened area has a tensile strength preferably greater than 1000MPa.

[0047] Figure 3 An alternative design variant is shown. Here, overlapping portions are formed in the respective transition regions 6, 7 and 8, so that the component blank is produced in such a way that the transition regions are produced in two layers. These transition regions are then connected by means of 12, as shown here. The tailored blank with overlapping portions is then produced in one press stroke, so that the entire rear side part is produced as a one-piece component.

[0048] Figure 4 An alternative design variant of the rear side part 1 is shown. This rear side part also has a C-pillar 2 and a D-pillar 3. The C-pillar 2 is in particular configured as a hat or U-shaped in cross section. A small wall thickness is configured in the region of the D-pillar 3. A minimum wall thickness is configured in the region of the wheel arch section 4. A large wall thickness is configured in the region of the C-pillar 2, as in the wheel arch and door sill connection region 13.

[0049] The upper region of the C-pillar 2 has a wall thickness of >1.6 mm and a tensile strength of >980 MPa. Furthermore, patches may optionally be provided.

[0050] The lower region of the C-pillar 2 preferably has a wall thickness of 1.2 mm to 1.6 mm starting from approximately the wheel arch height and a tensile strength of more than 980 MPa. The same characteristic values ​​preferably also apply to the D-pillar 3 .

[0051] The wheel arch 5 preferably has a wall thickness of >1.6 mm and / or a tensile strength of >980 MPa, in particular >1350 MPa, and is particularly preferably hardened.

[0052] In the region of the wheel arch section 4 , between the C-pillar 2 and the D-pillar 3 and the wheel arch 5 , a wall thickness of 0.8 mm to 1.6 mm and / or a tensile strength of <1350 MPa, in particular <980 MPa, is formed.

[0053] The steel types used can be used as examples for all variants of the invention. In particular, different types of steel can be combined with one another in tailored welded blanks. The corresponding strength ranges for hard or soft areas or strong or ductile areas can be derived from the following table. All alloy components are given in % by weight, with residual iron and impurities resulting from melting being added to the corresponding hardenable steel alloy.

[0054] 1 C Si Mn P S Al B 2 TWB-segment, selected from Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum 3 Hardenable steel Rm>1300MPa 0.19 0.25 0.1 0.4 1.1 1.4 0.02 0.005 0 0.06 0.004 0.1 4 22MnB5 Rm about 1500MPa 0.2 23 0.2 0.3 1.1 1.4 0.02 0.005 0 0.06 0.004 0.1 5 Hardenable steel Rm>1750MPa 0.31 0.37 0.1 0.6 1 1.5 0.025 0.02 0.1 0.001 0.004 6 34MnB5 Rm about 1900MPa 0.33 0.35 0.15 0.35 1 1.5 0.025 0.015 0.01 0.08 0.001 0.004 7 Ductility steel>450MPa 0.06 0.13 0.7 1.9 0.05 0.05 0.1 0.003 8 Hardenable Ductile Steel 800- 0.07 0.11 0.02 0.6 1.2 1.8 0.03 0.01 0.01 0.07 0.0007 0.002

[0055] 1 Cr Cu N Nb Ni Ti V Mo 2 TWB-segment, selected from Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum Minimum maximum 3 Hardenable steel Rm>1300MPa 0.3 0.1 0.05-Ti 0.02 0.1 0.01 0.1 0.35 4 22MnB5 Rm about 1500MPa 0.1 0.3 0.1 0.01 0.05-Ti 0.02 0.1 0.02 0.05 0.01 0.35 5 Hardenable steel Rm>1750MPa 0.08 0.35 0.2 0.2 0.1 0.2 0.002 0.05 0.35 6 34MnB5 Rm about 1900MPa 0.08 0.5-Mo 0.2 0.2 0.01 0.06 0.2 0.005 0.015 0.01 0.5-Cr 7 Ductility steel>450MPa 0.15 0.2 0.2 0.1 1.2 0.1 0.1 8 Hardenable Ductile Steel 800- 0.15 0.2 0.2 0.04 0.1 0.03 0.2 0.1 0.1

Claims

1. A rear side part (1) of a motor vehicle body, comprising a C-pillar (2), a D-pillar (3) and a wheel arch section (4), the wheel arch section being produced as a one-piece sheet metal formed component in one press stroke, wherein: The C-pillar (2) and the D-pillar (3) are shaped C-shaped, U-shaped or cap-shaped in cross section, characterized in that the side part (1) has adjacent regions having different tensile strengths and / or different wall thicknesses.

2. The side member (1) according to claim 1, characterized in that The side parts are manufactured as thermoformed and press-hardened components.

3. The side member (1) according to claim 1 or 2, characterized in that The high-strength region has a tensile strength of 1350 MPa or more.

4. The side part (1) according to any one of the preceding claims, characterized in that A soft region is constructed with a tensile strength Rm of less than 1000 MPa.

5. The side part (1) according to any one of the preceding claims, characterized in that A reinforcing patch is at least partially applied.

6. The side part (1) according to any one of the preceding claims, characterized in that The wheel arch section (4) is profiled in a partially spherical or spherical segment manner and / or the wheel arch section (4) is profiled in an L-shaped manner in cross section in the region of the wheel arch (5).

7. The side part (1) according to any one of the preceding claims, characterized in that The wheel arch section (4) has a lower tensile strength and / or an increased wall thickness in the region of the wheel arch (5).

8. The side part (1) according to any one of the preceding claims, characterized in that The wheel arch (5) is configured as a part of a circle and extends around an angle of more than 30°.

9. The side part (1) according to any one of the preceding claims, characterized in that Tailor-welded blanks are used as sheet metal blanks.

10. The side part (1) according to any one of the preceding claims, characterized in that The C-pillar (2) has a first section with a tensile strength >1350 MPa and a second section with a tensile strength <1000 MPa.

11. The side part (1) according to any one of the preceding claims, characterized in that The C-pillar (2), the D-pillar (3) and the wheel housing section (4) include openings.

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