Molded component, connection system having molded component, and method for producing molded component

Abstract

The profiled component (2) has a metallic component body (5) with a mounting hole (6) and a friction structure (7) surrounding the mounting hole. The component body (5) is made of boron alloy steel and is thermally modified and press-hardened. A friction structure (7) is produced in the stamping tool during thermal modification. At the same time, a mounting hole (6) is formed in the component body (5).

Description

Field of the Invention

[0001] The present invention relates to a formed component, a connection system having such a formed component, and a method for manufacturing a formed component. Background Art

[0002] Formed components with a metallic component body for connection to another formed component or assembly element within a connection system are used in various commercial and industrial applications.

[0003] In particular, in motor vehicle manufacturing, formed components made of metal or sheet metal are used, such as in the form of body components or structural components. The formed components are often connected to other formed components and / or additional parts and assembled into assemblies or motor vehicle components.

[0004] The connection of formed components and parts is usually achieved by bolt connection or screw connection. Here, the bolt is guided in or through an assembly hole and clamped with the provision of support. This is achieved in an application-specific manner in the case of inserting a gasket. The gasket added between the bolt head and the component body to be fixed with the bolt is used to distribute and transfer the force starting from the lower side of the bolt head to a larger surface of the component body. In the case of bolt penetration, depending on the application, a gasket is also provided under the counter nut.

[0005] Motor vehicle components are subject to strong static and dynamic loads during operation. Therefore, the high quality of the motor vehicle components themselves and their assembly, and in particular the connection points of the formed components or the connection points between the formed components, is indispensable, especially when the motor vehicle components are chassis components or body components. In the case where motor vehicle components are connected by thread technology, a good and anti-slip connection of the components to other connection points is mandatory.

[0006] For this purpose, the usual individual gaskets cannot provide optimal preconditions. Their assembly is also time-consuming.

[0007] There are also suggestions to dispense with the gasket and machine the surface of at least one component in the region of the clamping surface of the compression connection.

[0008] DE 10 2012 022 504 A1 discloses a compression connection of two components. These components have connection surfaces that abut against each other and are connected to each other when compressed, and at least one of these connection surfaces is provided with a surface structure for increasing the coefficient of friction. The surface structure is manufactured and hardened by means of a laser process or by means of stamping or cold pressing. The hardening can be achieved inductively or by means of a laser or electron beam process.

[0009] A positive-locking clamping connection belonging to the prior art and a method for manufacturing the same are known from DE 10 2007 016 643 A1. The positive-locking clamping connection includes a first metal clamping surface, a second metal clamping surface, and a clamping mechanism for clamping the clamping surfaces against each other. The first clamping surface constitutes a hardened surface microstructure with micro-protrusions and depressions, and is preferably surface-treated by sandblasting, shot peening, or stamping before hardening.

[0010] Known design solutions for connection points with mechanically generated surface structures in the connection or clamping area between mating parts have withstood the test in practice and are well-suited for various application purposes. However, there is also potential for improvement here, not only in terms of the functionality of the connection points, but also in terms of the rationality of the shaped components and the connection systems having such shaped components. There is also a general pursuit of implementing the shaped components (including their connection points) in an effective lightweight manner. Summary of the Invention

[0011] Starting from the prior art, the task underlying the present invention is to improve, in terms of manufacturing technology and functionality, shaped components having a metallic component body and a friction structure, to provide a connection system having such shaped components, and to provide a rational and advantageous method for manufacturing the shaped components.

[0012] The solution to the substantial part of the task lies in the shaped component according to claim 1.

[0013] A connection system having a shaped component according to the present invention is the subject of claim 7.

[0014] The process technology part of the task is solved by the method for manufacturing a shaped component according to claim 8.

[0015] The design solutions and variants of the features of the shaped component and the process steps can be derived from the description and the drawings, which technically advantageously design or improve the present invention individually or in combination.

[0016] The shaped component according to the present invention has a metallic component body with an assembly hole and a friction structure surrounding the assembly hole. The friction structure is stamped or embossed and hardened.

[0017] According to the present invention, the component body is made of quenchable steel and is hot-modified (hot-deformed / hot-formed) and press-hardened, wherein the friction structure is generated during the hot forming of the component body, in particular by stamping.

[0018] "Stamping a friction structure in a stamping tool" is achieved in a stamping tool on a steel sheet heated to the thermoforming temperature by material displacement, such that the friction structure has protrusions and / or depressions. The component body and the friction structure produced thereon are clamped in a cooled stamping tool and quenched by cooling.

[0019] The formed component or its metallic component body is made of quenchable steel. The friction structure is produced integrally on the component body in a material-uniform manner. This is achieved by stamping in a stamping tool during component body modification and die quenching.

[0020] In particular, the quenchable steel is a boron alloy steel, preferably a manganese boron steel, such as 22MnB5.

[0021] In particular, the friction structure has friction elements produced by stamping.

[0022] Particularly advantageously, the friction elements are designed in the form of ribs extending radially outwards from the mounting hole. The ribs have an average height measured over their length of 0.05 to 0.9 mm, in particular 0.1 to 0.4 mm.

[0023] The friction elements can be designed as ribs, waves, dots or spheres. The friction elements can completely or partially surround the mounting hole.

[0024] The friction structure is provided and specified to increase the friction between the mating parts or clamping surfaces within the connection system. The spatial design and arrangement of the friction elements within the friction structure are coordinated with the connection points within the connection system.

[0025] The friction structure can have ribs produced by stamping, which have an annular course. Here, the annular friction elements can be arranged concentrically around the mounting hole.

[0026] Particularly advantageously, the friction structure has friction elements produced by stamping, in the form of ribs extending radially outwards from the mounting hole. In particular, the ribs extend radially, that is to say, they have a radial course with respect to the midpoint of the mounting hole. The ribs are protrusions relative to the regions adjacent to the adjacent ribs. The ribs provide the necessary friction and withstand high loads when the formed component is tensioned within the connection system. In this case, the friction structure produced and press-quenched in a stamping tool proves to be advantageous.

[0027] A friction structure that is advantageous in practice has a hardness (Vickers hardness) of 350 HV to 550 HV, in particular 400 HV to 500 HV.

[0028] In an advantageous embodiment of the formed component for practice, the component body has a wall thickness between 1.0 mm and 3.5 mm, this wall thickness range including 1.0 mm and 3.5 mm.

[0029] To manufacture a shaped part according to the present invention, a quenchable steel sheet or a semi-finished product made of a quenchable steel sheet, in particular a sheet made of manganese boron steel, is hot-shaped and press-hardened into a component body in a stamping tool. When hot-forming in the stamping tool, a friction structure is provided in the area of the steel sheet. This is achieved by stamping in the stamping tool.

[0030] An area with a friction structure is stamped around the assembly hole.

[0031] Particularly preferably, when hot-forming in the stamping tool, an assembly hole is manufactured.

[0032] The manufacture of the friction structure and the manufacture of the assembly hole are preferably realized in parallel in time in the stamping tool.

[0033] The manufacture of the shaped component is achieved by die quenching of the steel sheet which may be pre-shaped if necessary. Die quenching is known in the art as press hardening. During press hardening or die quenching, the sheet made of manganese boron steel is heated to a temperature above the specific austenitizing temperature of the steel, placed in a stamping tool, and hot-shaped into a shaped component, wherein the sheet cools during shaping. With the stamping tool clamped, the shaped component is quenched by cooling.

[0034] For hot-forming, in particular, the steel sheet or the semi-finished product is heated to a temperature above 750 °C, in particular to a temperature above the Ac3 temperature of the quenchable steel.

[0035] The shaped component according to the present invention is in particular a motor vehicle component. The shaped component can be used as a part of an axle, an axle component or a shaft body such as a subframe and a unit support.

[0036] The motor vehicle component can be made of a steel structure, preferably made of shell-shaped shaped components connected to each other, at least one of these shaped components being designed according to the present invention and having a connection point with an assembly hole. At least one assembly hole has a friction structure surrounding the assembly hole, which is manufactured during the hot-forming of the component body and is press-hardened together with the component body in a stamping tool.

[0037] The present invention advantageously integrates the manufacture of the friction structure and the hardening into the shaping and hardening process of the component body. This is particularly effective and advantageous. By integrating the friction structure into the component body and through the press hardening process, an optimization of the component weight is also achieved. Additional spacers or surface structures produced by means of material coating are dispensed with. In this way, a contribution can be made to lightweight design.

[0038] In order to reduce weight, especially in the field of battery electric vehicles, components of the white body are increasingly implemented as hot-formed parts, which, due to their higher strength, enable material savings and thus weight reduction. According to the invention, the friction structure is stamped into the component body during the hot-forming process and simultaneously quenched with the component body by cooling in a stamping tool.

[0039] When using the formed component within a connection system, assembly or fitting with other formed components and / or additional parts is achieved. This is accomplished by bolted connections / screw connections. When assembling the formed component according to the invention with a particularly soft counterpart or mating part, such as an axle carrier, the friction structure can be engraved into the counterpart or the second mating part.

[0040] Within the scope of the invention, the process steps of hot-forming, stamping, and quenching of the friction structure are all completed in one process step and one stamping tool. Post-quenching of the friction structure is not required. Through this process, a hardness in the range of 350 to 550 HV, especially 400 HV to 500 HV, is achieved. The friction structure preferably has a uniform hardness distribution, which also uniformly transitions into the area surrounding the friction structure. This avoids critical mechanical notches and, while ensuring a high level of wear protection, avoids the risk of cracks or component fractures. Within the scope of the invention, a uniform hardness distribution within the friction structure is understood to mean that the hardness fluctuations therein preferably do not exceed 100 HV, especially are less than 50 HV. Also preferably, the hardness of the friction structure differs from the hardness of the surrounding area by no more than 100 HV. Description of the Drawings

[0041] The present invention will be supplemented and described below based on an embodiment. The figures show:

[0042] Figure 1 A motor vehicle component in the form of a subframe is shown in a perspective view;

[0043] Figure 2 A partial cross-sectional view of the motor vehicle component is shown, with an illustration of the connection points in the motor vehicle component, and

[0044] Figure 3 A partial cross-sectional view of the friction structure on the motor vehicle component is shown technically schematically. Detailed Description of the Invention

[0045] Figure 1 A motor vehicle component 1 in the form of a subframe is shown in a perspective view.

[0046] The motor vehicle component 1 is implemented as a sheet metal shell structure and has a shell-shaped first formed component 2 and a shell-shaped second formed component 3. In addition, the motor vehicle component 1 has a side vault element 4. The formed components 2 and 3 and the vault element 4 are implemented as sheet metal formed parts and are joined to form the motor vehicle component 1.

[0047] The first formed component 2 has a component body 5 with assembly holes 6, which are provided as connection points.

[0048] The assembly holes 6 in the component body 5 of the first formed component 2 are surrounded by a friction structure 7. The friction structure 7 has protrusions and depressions. The friction structure 7 is integrally formed on or in the component body 5 by stamping in a material-uniform manner. This is achieved during the process of manufacturing the component body 5 by thermoforming technology in a stamping tool. In the stamping tool, during the thermoforming process, the friction structure 7 is stamped in the region of the component body 5 surrounding the assembly holes 6. When clamped in the stamping tool, the component body 5 and the friction structure 7 are press-hardened in the stamping tool.

[0049] Figure 2 The illustration of shows a cross-section of the motor vehicle component 1 in the region of the connection point with the assembly holes 6 and the friction structure 7.

[0050] Assembly holes 6 are provided in the component body 5 of the shell-shaped first formed component 2, and the assembly holes are surrounded radially by the friction structure 7. The lower second formed component 3 has assembly holes 8. A sleeve body 9 is arranged below the upper assembly holes 6 in the first formed component 2. The through holes 10 of the sleeve body 9 communicate with the upper assembly holes 6. The sleeve body 9 passes through the lower assembly holes 8 and engages with both the first formed component 2 and the second formed component 3 in a material-locking manner.

[0051] The friction structure 7 completely surrounds the assembly holes 6 in the component body 5 of the first formed component 2 in a ring-shaped or circular shape.

[0052] An enlarged partial cross-sectional view of the friction structure 7 is shown in Figure 3 .

[0053] The friction structure 7 has friction elements in the form of ribs 11, which are manufactured by stamping in a stamping tool during the forming of the component body 5. The ribs 11 extend outward from the assembly holes 6. The friction structure 7 has a plurality of radially arranged, straight-extending ribs 11, which extend from the radial inside to the radial outside with respect to the assembly holes 6. The ribs 11 are triangular in cross-section and widen towards their base. The straight sides 12 of the ribs 11 form an angle with each other and lead into the rib peaks 13. The ribs 11 have an average height H measured over their length of 0.1 mm to 0.4 mm, in particular approximately 0.3 mm.

[0054] The assembly hole 6 in the component body 5 of the formed component 2 is made in a stamping tool during the hot forming of the component body 5. To manufacture the formed component 2, a sheet made of boron alloy steel, in particular manganese boron steel, or a semi-finished product preformed from this sheet is heated to a temperature above the specific austenitizing temperature of the boron alloy steel. Then, the steel sheet or the semi-finished product is placed into the stamping tool and hot-formed into the formed component between the top die and the bottom die of the stamping tool. Here, the assembly hole 6 is made in the component body 5, and the friction structure 7 is stamped out in the area of the component body 5 surrounding the assembly hole 6. During forming, the component body 5 is clamped in the stamping tool, and the formed component is quenched by cooling.

[0055] It goes without saying that the shell-shaped second formed component 3 can also be manufactured by die quenching or press quenching. Here, the assembly hole 8 can be made in the stamping tool, and optionally, the friction structure 7 surrounding the assembly hole 8 can also be manufactured and quenched by stamping in the stamping tool.

[0056] The friction structure 7 has a hardness ranging from 350 HV to 550 HV, in particular from 400 HV to 500 HV, as determined by a hardness test according to Vickers hardness. Since the component body 5 and the friction structure 7 on the component body 5 are generated during the manufacture of the formed component by die quenching or press quenching, the component body 5 of the formed component 2 also has a corresponding hardness in the range between 350 HV and 550 HV, in particular from 400 HV to 500 HV.

[0057] The friction structure 7 increases the friction in the surface area surrounding the assembly hole 6, thereby better and more durably holding the threaded element for assembly and the resulting threaded connection, even in the case of strong static and dynamic loads during the operation of a motor vehicle. List of reference numerals

[0058] 1 Motor vehicle component

[0059] 2 First formed component

[0060] 3 Second formed component

[0061] 4 Vault element

[0062] 5 Component body

[0063] 6 Assembly hole

[0064] 7 Friction structure

[0065] 8 Assembly hole

[0066] 9 Sleeve body

[0067] 10 Through hole

[0068] 11 Rib

[0069] 12 sides

[0070] 13 rib peaks

[0071] Average height of H11

Claims

1. A molded component having a metallic component body (5) with a mounting hole (6) and having a friction structure (7) surrounding the mounting hole (6), wherein: The friction structure (7) is stamped and hardened, characterized in that the component body (5) is made of hardenable steel and is hot-formed, wherein the friction structure (7) is produced and the component body (5) is press-hardened.

2. The method according to claim 1, characterized in that The friction structure (7) has friction elements produced by stamping.

3. The molded component according to claim 2, characterized in that The friction element is designed in the shape of ribs, waves, dots or balls.

4. The molded component according to any one of claims 1 to 3, characterized in that The friction structure (7) has a hardness of 350 HV to 550 HV, in particular 400 HV to 500 HV.

5. The molded component according to any one of claims 1 to 4, characterized in that The component body (5) has a wall thickness between 1.0 mm and 3.5 mm, the wall thickness range being 1.0 mm and 3.5 mm inclusive.

6. The molded component according to any one of claims 1 to 5, characterized in that The component body is made of boron alloy steel.

7. A connection system comprising a profiled component according to any one of claims 1 to 6.

8. A method for producing a shaped component, wherein: A hardenable steel sheet or a semi-finished product made of a hardenable steel sheet is hot-formed in a punching tool and press-hardened to form a component body (5), characterized in that during the hot forming in the punching tool, a friction structure (7) is provided on areas of the steel sheet.

9. The method according to claim 8, characterized in that The region with the friction structure (7) is produced around the mounting opening (6).

10. The method according to claim 9, characterized in that The assembly holes (6) are produced during thermoforming.

11. The method according to claim 9 or 10, characterized in that: The production of the friction structure (7) and the production of the assembly opening (6) are carried out in parallel in the punching tool.

12. The method according to any one of claims 8 to 11, characterized in that For hot forming, the steel sheet or the semi-finished product is heated to a temperature T above 750° C., in particular to a temperature above the Ac3 temperature of hardenable steels.

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