Method for separating at least two components held together and fastening system

Abstract

A method for separating at least two held-together components (1, 2) using an auxiliary body (8), wherein a connecting element (5) comprises a connecting body (4) which is connected to a first component (1) and extends through a second component (2), wherein the connecting body (4) has a retaining head (6) at an end projecting from the second component (2) which holds the two components (1, 2) together, wherein an auxiliary body (8) is attached to the retaining head (6) which is subjected to a release force to loosen the holding of the two components (1, 2) in order to separate the retaining head (6) from the connecting body (4), and wherein the connecting body (4) is designed as a shaft, characterized in that the retaining head (6) is integrally connected to the connecting body (4), wherein the first component (1) is a steel component, and wherein the second component (2) is an aluminum component.wherein the connecting element (5) is a friction element, wherein the connecting element (5) is materially bonded to the first component (1), wherein the retaining head (6) is conditionally detachably connected to the connecting body (4), wherein the retaining head (6) is positively bonded to the second component (2) to represent the cohesion of the two components (1, 2), wherein the auxiliary body (8) is materially bonded to the retaining head (6), wherein the auxiliary body (8) is a threaded bolt (9), and wherein the connection between the auxiliary body (8) and the retaining head (6) is stronger than the connection between the connecting body (4) and the retaining head (6).

Description

[0001] The invention relates to a method for separating at least two components held together according to the preamble of claim 1. The invention further relates to a fastening system with at least two components held together which can be separated from each other according to a method described above.

[0002] German patent DE 101 56 403 C1 discloses a fastening system for attaching a body to a metallic component, in particular for attaching a body to a metal sheet such as a body panel of a motor vehicle, comprising a metallic threaded bolt which is attached to a component by means of short-time arc welding, and a fastening nut which is screwed onto the threaded bolt and by means of which the body is attached to the component, wherein the strength of the welded joint between the component and the threaded bolt and the strength of the threaded bolt itself are coordinated in such a way that when a torque exceeding that which is normally applied when screwing the fastening nut onto the threaded bolt is applied, it is ensured that the threaded bolt breaks.before the component breaks. European patent EP 1 549 858 B1 discloses a bolt-to-structure arrangement comprising a weldable connecting element with a fastening head having a solid cylindrical pin, wherein a nut is designed to break at a limit load. International patent application WO 2012 / 031 982 A1 discloses a method for connecting at least two components, comprising the following steps: heating a bolt made of a thermoplastic material so that it becomes at least partially deformable; guiding the bolt made of the thermoplastic material through an opening in the second component, wherein the bolt is connected to the first component or is previously guided as a separate component through a first opening in the first component; pressing the heated bolt out of the thermoplastic material so that the bolt bears against the wall of the opening in the second component.wherein the wall is designed as an internal thread, or insertion of the bolt into a sleeve having an internal thread and pressing of the bolt so that it engages with the internal thread of the sleeve, wherein the bolt is heated before being passed through the opening in the second component or after being inserted into the opening in the second component or into the sleeve, wherein the components are made of different materials.

[0003] The object of the invention is to simplify the separation, as required, of at least two components held together by means of a connecting element according to the preamble of claim 1.

[0004] The problem is solved by a method with the features of new claim 1 and by a fastening system with the features of claim 3. The two components are parts made of different materials. These parts are preferably body-in-white components of a motor vehicle body. The connecting body is, for example, designed as a shaft extending from the first component through the second component. The connecting body has, for example, the shape of a straight circular cylinder. The retaining head is designed, for example, in a manner similar to a nail head or screw head. The retaining head has, for example, the shape of a circular disc. The retaining head is integrally connected to the connecting body. The auxiliary body enables or at least simplifies the engagement of a tool at an end of the auxiliary body facing away from the retaining head.The tool applies the release force, which is transmitted to the retaining head via the auxiliary body. The auxiliary body preferably has an elongated shape. The claimed method deliberately incorporates an additional component and an additional work step to ensure quick and easy release of the retaining head, particularly without damaging either component during the process. After the retaining head is released, the two components are no longer held together by it. This allows, for example, a damaged component to be replaced during a repair. The two components are preferably sheet metal parts that lie flat against each other. Due to the different materials, these flat sheet metal parts are not as easy to join securely as sheet metal parts made of the same material.The claimed method significantly simplifies the separation of the joined components. The friction element is, for example, a friction weld element or a friction nail. When the friction element is connected to the first component, heat is generated by friction to weld an end of the connecting element facing the first component to the first component. For stable cohesion of the two components, a plurality of friction elements are preferably bonded to the first component. A free end of the connecting element is welded to the first component, preferably by friction welding. This welding process can advantageously be carried out largely automatically in large quantities. The connecting element penetrates the second component. If the connecting element is a friction nail, then the connecting element also penetrates the first component.Because the retaining head is conditionally detachable from the connecting body, and the retaining head is positively locked to the second component to demonstrate the cohesion of the two components, a stable connection between components made of different materials is achieved in a simple manner. Furthermore, the separation of the components is significantly simplified. The auxiliary body is preferably welded to the retaining head. Advantageously, a free end of the auxiliary body is welded to a surface of the retaining head. Welding the auxiliary body can advantageously be carried out using a conventional stud welding machine. To simplify the welding of the auxiliary body, the retaining head is advantageously designed with a geometry that is easy to weld. The threaded stud is simple and inexpensive to manufacture. Advantageously, a standard part is used as the auxiliary body.The threaded bolt is combined with a nut, which is advantageously also a standard part. The loosening force, in particular the torque used for loosening, can be applied to the auxiliary body using a simple tool via the nut screwed onto a free end of the threaded bolt. The loosening force, in particular the torque required for loosening, is transferred to the retaining head via the attachment of the auxiliary body to the retaining head, in particular the material-fit connection between the auxiliary body and the retaining head. The conditionally detachable connection between the retaining head and the connecting body of the fastener is designed such that the retaining head is reliably sheared off the connecting body without the connecting body detaching from the first component and without damaging the components.By making the connection between the auxiliary body and the holding head stronger than the connection between the connecting body and the holding head, it is ensured that the holding head can be separated from the connecting body if necessary, for example for repair work on or replacement of at least one of the components, in order to separate the components from each other without damage.

[0005] A preferred embodiment of the method is characterized in that the auxiliary body is rotated with the retaining head in order to shear the retaining head off the connecting body. A conventional screwdriving tool, such as a ratchet, a ratchet wrench, or a spanner, can advantageously be used to rotate the auxiliary body with the retaining head. The desired loosening force or torque can then be applied manually in a repair shop via a suitably designed lever arm.

[0006] The invention further relates to a fastening system with at least two components held together, wherein an auxiliary body is attached to a holding head such that the components can be separated from one another according to a previously described method. The fastening system significantly simplifies the repair or replacement of at least one of the components.

[0007] The invention may also relate to at least one component, a connecting element and / or an auxiliary body for such a fastening system. The aforementioned parts are separately marketable.

[0008] Further advantages, features, and details of the invention will become apparent from the following description, in which various exemplary embodiments are described in detail with reference to the drawing. The drawing shows: Fig. 1 a schematic sectional view of a fastening system with two components held together by means of a connecting element when attaching an auxiliary body to a holding head of the connecting element; Fig. 2 the fastening system made of Fig. 1 with a nut screwed onto the auxiliary body; and Fig. 3 the fastening system made of Fig. 2 after the auxiliary body with the holding head has been detached from a connecting body of the connecting element.

[0009] In the Fig. 1, Fig. 2 to Fig. Figure 3 shows a fastening system 10 with two components 1 and 2 in different states. The first component 1 is a body-in-white 11 of a motor vehicle. The body-in-white 11 is made of steel. The second component 2 is a body-in-white 12 of the motor vehicle. The body-in-white 12 is made of aluminum.

[0010] The two components are held together by means of a connecting element 5. The connecting element 5 is representative of a multitude of connecting elements with which the two preferably planar body parts 11 and 12 of the motor vehicle are held together.

[0011] The connecting element 5 comprises a connecting body 4 that extends through a through-hole 3 in the second component 2. The connecting body 4 is metallurgically bonded to the first component 1 at one end facing the first component 1, preferably by welding.

[0012] At one in the Fig. 1 and Fig. 2. A retaining head 6 is attached to the upper end of the connecting body 4. The retaining head 6 of the connecting element 5 is conditionally detachable, for example, integrally connected to the connecting body 4 of the connecting element 5.

[0013] Conditionally detachable means, firstly, that the material-bonded connection between the connecting body 4 and the first component 1 is stronger or more stable than, for example, the one-piece connection between the retaining head 6 and the connecting body 4 of the connecting element 5. Thus, the connecting body 4 remains attached to the first component 1 if the retaining head 6 is subsequently sheared off.

[0014] The holding head 6 is located in the Fig. 1 and Fig. 2 from above, at the second component 2. In this way, the two components 1 and 2 are held stably together with the help of the retaining head 6 and the connecting body 4, which is materially bonded to the first component 1.

[0015] The connecting element 5 is a friction welding element or a friction nail. Connecting element 5 is used in body-in-white construction as part of a permanent joining technique using friction welding or friction nailing to join the two components 1 and 2.

[0016] In friction element welding or friction nailing, the connecting element 5 with the connecting body 4 first penetrates the material in the Fig. 1 and Fig. 2. Aluminum material of the second component 2 is arranged at the top or head end. Subsequently, the free end of the connecting body 4 is welded to the component in the Fig. 1 and Fig. 2 the first component 1 arranged below, which is made of a steel material.

[0017] During friction nailing, the connecting body 4 also penetrates the first component 1 located below. After the joining process, the friction welding element or the friction nail is welded to the first component 1 located below. The second component 2, located above or at the head, is positioned between the first component 1 and the retaining head 6 of the connecting element 5 after the joining process and is thus positively locked to the first component 1.

[0018] This ensures that components 1 and 2 are held securely together. During repairs or maintenance, it may be necessary to separate components 1 and 2, which requires breaking the bonded connection, particularly the friction weld or friction nail connection.

[0019] In Fig. 1 is indicated by a lightning symbol 13, which signifies that an auxiliary body 8 is attached to the top of the holding head 6. The auxiliary body 8 is a threaded bolt 9, which is connected to a Fig. The end 1 located below is welded onto the retaining head 6. The threaded bolt 9 has a collar 7 which forms a stop for a Fig. Figure 2 shows the nut 14, which is screwed onto the threaded bolt 9.

[0020] Before creating the metallurgical bond between the auxiliary body 8 and the retaining head 6 of the connecting element 5, the retaining head 6 is advantageously ground to a bright finish. Then the auxiliary body 8, also referred to as a grounding stud, is welded onto the ground retaining head 6, for example, using a stud welding machine.

[0021] In Fig. Figure 2 shows that to separate the two components 1 and 2, the nut 14 is first screwed onto the threaded bolt 9 until it comes to rest against the collar 7. The nut 14, thus secured, can then be loosened using a tool such as a wrench or ratchet with a suitable socket, applying a loosening force or torque.

[0022] The loosening force or torque causes the nut 14 to rotate until the retaining head 6 of the connecting element 5 shears off from the connecting body 4, as can be seen in Fig. 3. The connecting body 4 remains firmly connected to the first component 1.

[0023] Without the holding head 6, the second component 2 can be detached from the first component 1. The connecting body 4 remaining on the first component 1 can be removed in a further machining step, for example by machining. Any element shaft remaining after friction nailing can remain in the lower component 1, with the top surface of the first component 1 being advantageously ground flat.

[0024] The connecting element 5, i.e., the friction welding element or the friction nail, is advantageously made of the same steel material as the first component 1. This offers, among other advantages, that during machining, particularly machining, of the first component 1 to remove the connecting body 4 remaining after the retaining head 6 has sheared off, only pure steel chips are produced.

[0025] The retaining head 6 of the connecting element 5 is advantageously conditionally detachable and connected to the connecting body 4 of the connecting element 5. This conditionally detachable connection can be formed in one piece. The conditionally detachable connection between the retaining head 6 and the connecting body 4 of the connecting element 5 is weaker than the metallurgical connection between the auxiliary body and the retaining head 6. This can be achieved, for example, by appropriately designing the diameter of the connecting body 4 and the size or strength of the weld between the retaining head 6 and the auxiliary body 8.

[0026] Furthermore, the material-bonded connection between the connecting body 4 and the first component 1 is advantageously stronger than the conditionally detachable connection between the connecting body 4 and the retaining head 6 of the connecting element 5. This ensures that the connecting body 4 does not detach from the first component 1 when the retaining head 6 shears off. In this way, damage to the first component 1 and, if applicable, also to the second component 2 can be reliably prevented.

Claims

[1] Method for separating at least two components (1, 2) held together by means of an auxiliary body (8), wherein a connecting element (5) comprises a connecting body (4) which is connected to a first component (1) and extends through a second component (2), wherein the connecting body (4) has a retaining head (6) at an end projecting from the second component (2) which holds the two components (1, 2) together, wherein an auxiliary body (8) is attached to the retaining head (6) which is subjected to a release force in order to release the holding of the two components (1, 2) in order to separate the retaining head (6) from the connecting body (4), and wherein the connecting body (4) is designed as a shaft, characterized bythat the retaining head (6) is integrally connected to the connecting body (4), wherein the first component (1) is a steel component, wherein the second component (2) is an aluminum component, wherein the connecting element (5) is a friction element, wherein the connecting element (5) is materially bonded to the first component (1), wherein the retaining head (6) is conditionally detachably connected to the connecting body (4), wherein the retaining head (6) is positively bonded to the second component (2) to demonstrate the cohesion of the two components (1,2), wherein the auxiliary body (8) is materially bonded to the retaining head (6), wherein the auxiliary body (8) is a threaded bolt (9), and wherein the connection between the auxiliary body (8) and the retaining head (6) is stronger than the connection between the connecting body (4) and the retaining head (6). [2] Method according to claim 1, characterized by, that the auxiliary body (8) is twisted with the holding head (6) in order to shear the holding head (6) off the connecting body (4). [3] Fastening system (10) with at least two components (1,2) held together, wherein an auxiliary body (8) is attached to a holding head (6) such that the components (1,2) can be separated from each other according to a method according to one of the preceding claims.

Images