Self-piercing rivets and self-piercing riveted joints

Abstract

The self-piercing rivet (1) is used for producing a joining joint, has a basic shape of a rectangle or a trapezoid, and has a rivet head (2) and a rivet shank (3). The rivet shank comprises two shank legs (4) which are spaced apart from each other and which protrude perpendicularly from the rivet head (2) in one direction. The rivet head (2) and the shank legs (4) define a recess (7), and an opening (8) of the recess opens to the side opposite the rivet head (2). The shank legs (4) taper in width from the rivet head (2) to a shank leg base (9), but remain constant in height, wherein the shank leg bases (9) each have a wedge-shaped end (23) which is arranged on the outside near a side surface (5) or near the recess (7). The shank legs (4) are adapted to unfold inwards or outwards during joining.

Description

Technical Field

[0001] This disclosure relates to self-piercing rivets and self-piercing riveted joints. The self-piercing rivet is used to produce a joint and has a rivet head and a rivet shank extending in the form of two legs. Background Technology

[0002] Self-piercing rivets can be used to connect two parts. Self-piercing riveting does not require pre-drilling of the parts. For example, solid rivets or semi-tubular rivets can be used. In self-piercing riveting using semi-tubular rivets, the rivet is forced through the first part and deforms the second part (especially sheet metal). The rivet expands and the second part forms the closed head of the rivet. During riveting, the joint rests on a die that acts as a counterholder.

[0003] For example, US6325584B1 discloses a self-piercing rivet, wherein the rivet includes a rivet head (also called a flange) having a large diameter and a shank having a hollow cavity extending inward from the flange, wherein the end of the shank pierces multiple workpieces, deforms and expands radially outward, and remains inside the final workpiece without passing through the final workpiece.

[0004] Steel plates can be joined together using steel semi-hollow rivets. These steel rivets have pointed feet to allow easy insertion into the parts to be joined. For example, DE4431769A1 describes a self-piercing rivet with pointed feet, which is used to join high-strength sheets and is typically made of hardened and tempered steel.

[0005] EP0833063A1 describes a semi-hollow rivet made of a lightweight metal for connecting lightweight metal components. Compared to commonly used self-piercing rivets made of steel, this lightweight metal semi-hollow rivet has a blunt rivet foot instead of a pointed one. Typically, this lightweight metal semi-hollow self-piercing rivet has an ultimate tensile strength of approximately 450 N / mm². Therefore, this tensile strength is significantly lower than that of semi-hollow self-piercing rivets made of steel (which typically have a tensile strength of approximately 1400 N / mm²). Due to this high tensile strength, steel rivets can penetrate and connect ordinary steel plates with tensile strengths up to 500 N / mm².

[0006] US7,736,110B2 discloses a U-shaped staple for securing metal sheets together, comprising a section of circular metal wire bent at the end to form spaced-apart cantilevered metal legs. Each leg has a metal piercing tip at its end, such that a first sheet is completely pierced and a second sheet is at least partially pierced, thereby allowing the leg to continue unfolding to an open position during piercing, in which the leg is anchored in the metal sheets, thus securing the metal sheets together. Due to the use of a circular metal wire, undesirable deformation of the legs cannot be prevented during actuation.

[0007] The well-known problem with semi-hollow self-piercing rivets is that their production is complex and costly. Additionally, significant force is required to install them. When large expansion occurs, especially if the lower material (on the die side) is thin, known semi-hollow self-piercing rivets can produce significant undercut (also known as interlocking). However, excessive expansion increases the risk of breakage. Another disadvantage is that when semi-hollow self-piercing rivets are installed, they cause a significant amount of material to move outwards, meaning a larger edge distance is required for the connection. Utility Model Content

[0008] The purpose of this invention is to provide a self-piercing rivet that is easy to manufacture, adaptable, and readily adaptable to different types of applications, and does not have the disadvantages of existing technologies.

[0009] A self-piercing rivet for producing connecting joints has a basic rectangular or trapezoidal shape and includes a rivet head and a rivet shank. The rivet shank comprises two legs spaced apart from each other and projecting perpendicularly from the rivet head in one direction. The self-piercing rivet has a recess defined by the rivet head and the legs, with an opening opening to a side opposite the rivet head. The legs taper in width from the rivet head towards their bases, but remain constant in height, particularly in height, both in length and width. Each leg base has a wedge-shaped end disposed near a side surface or near the opening. The legs are adapted to extend inward or outward during connection. The self-piercing rivet according to this invention is inexpensive to manufacture and easy to store. Furthermore, tests have shown that this self-piercing rivet can be used to connect various structural components and achieve stable connections. The self-piercing rivet is particularly relevant for sheet metal applications, especially in the automotive industry. Another advantage of the self-piercing rivet according to this invention is that it advantageously exhibits significant deformation only in one direction and very slight deformation only in another direction. In particular, this allows for smaller margins during connection. Advantageously, the self-piercing rivet according to this invention can be used to connect two or more components.

[0010] In a preferred embodiment, the two side surfaces of the shank leg are arranged parallel to each other. This allows for the cost-effective production of self-piercing rivets while simultaneously ensuring uniform insertion into the component with good material displacement. In an alternative embodiment, the side surfaces of the shank leg may have a slight angle.

[0011] In one embodiment, the legs are designed such that, when the self-piercing rivet is installed, the legs extend outward or inward in a plane relative to the longitudinal central axis of the self-piercing rivet. This means that the direction of leg extension can be advantageously defined due to the defined material properties and the geometry of the self-piercing rivet. This deformation of the legs achieves optimal flow behind the component material without penetrating it, and ensures a stable connection. Another advantage is that the extension of the legs prevents them from leaving, for example, the final component, and thus prevents damage to the connected workpiece.

[0012] The advantageous wedge shape at the base of the shank allows for influence over the deployment of the self-piercing rivet. For example, the deployment can be influenced by modifying the angle of the wedge shape. By design, the shank of the self-piercing rivet deploys outward or inward, i.e., toward or away from the longitudinal axis of the self-piercing rivet. In the context of this invention, the term "deployment" refers to the movement of the shank toward or away from the longitudinal axis of the self-piercing rivet during connection. In the context of this invention, the movement of the shank in the longitudinal direction can also be referred to as "compression."

[0013] In one embodiment, the width of the rivet head is the same as the width of the rivet shank. More preferably, the self-piercing rivet has a substantially constant height based on its overall linear expansion range and lateral expansion range. As a result, the self-piercing rivet has a constant stiffness across its dimensional range. U-shaped rivets known in the prior art cannot ensure constant deformation due to their construction from wires with a circular cross-section. This advantageous design also simplifies the production of self-piercing rivets. Preferably, the self-piercing rivet's range in the height direction is smaller than its range in the length and width directions. In the context of this invention, the terms thickness and height are used interchangeably.

[0014] The self-piercing rivets are preferably made of sheet metal or produced by an extrusion molding process. By using different types of sheet metal with different physical or chemical properties, optimized self-piercing riveting can be provided for the application. Materials that cannot be cold-formed, such as stainless steel, can be used. This means that the material does not need to be coated. Hardened sheet metal can also be used as the material for self-piercing rivets. Preferably, the self-piercing rivets are stamped from sheet metal or manufactured by an extrusion process. Self-piercing rivets can also be cut from sheet metal using cutting techniques such as laser cutting. Furthermore, rolling processes can be used to produce self-piercing rivets. Preferred manufacturing processes allow for easy modification of the surface profile of the self-piercing rivets.

[0015] In one embodiment of the self-piercing rivet, the rivet head may have a flange that projects laterally above the rivet shank. This flange may be designed as a countersunk head or a protruding head. This can result in a joint with better load-bearing capacity.

[0016] Furthermore, preferably, at least one surface of the self-piercing rivet has at least a partial structural feature. For example, the surface of the self-piercing rivet can be a side surface, a front or rear surface, the upper side of the rivet head, or the surface surrounding the recess. Such structural features can be, for example, recesses, ridges, corrugations, protrusions, or any other element or variation of a planar surface. For the purposes of this invention, a side surface refers to a surface on the longitudinal side. For shapes deviating from the basic rectangular shape, such as a square, a side surface may also be referred to here. Recesses in the form of grooves, notches, etc., can exist, affecting flow behind the structural components to be connected. Furthermore, recesses or ridges arranged at intervals on one side of the self-piercing rivet may be present.

[0017] A recess exists between the legs, defined by a rivet head. In one embodiment, the upper portion of the recess between the legs is rounded in the direction toward the rivet head. However, in another embodiment, the upper portion of the recess may also be tapered. Recesses, ridges, edges, etc., may be arranged at intervals on the side surface of the legs defining the recess.

[0018] The present invention also relates to a method for connecting at least two structural components, each of which is designed to be flat on at least one connecting surface, wherein a first structural component contacts a connecting surface of a second structural component via the connecting surface of the first structural component, wherein the aforementioned self-piercing rivet is placed on the connecting surface of the first structural component by means of an mounting device and the self-piercing rivet connects the first structural component and the second structural component to each other, wherein the legs extend inward or outward during connection. This method enables the efficient connection of two structural components using self-piercing rivets. A significant advantage is that the design of the self-piercing rivet allows dissimilar materials to be joined together. Preferred designs and advantages of self-piercing rivets are also applicable to this method.

[0019] Preferably, prior to joining, the first component and / or the lower component or the second component in the region of the joining surface is heat-treated such that a heat-affected zone is preferably formed on the joining surface of at least the first component, and the first component and / or the lower component or the second component is heated such that the strength of the first component and / or the lower component or the second component in the heat-affected zone is reduced. This treatment can be performed using a plasma torch to deliver plasma. This beneficial pretreatment of at least one region of at least one component is disclosed, for example, in WO2018 / 055210A1, the disclosure of which is expressly incorporated herein by reference. However, other pretreatment methods are also possible, such as using lasers or induction. The lower component or the second component is a component disposed on the mold side.

[0020] The present invention also relates to a self-piercing riveting joint having at least two structural components connected to each other by the aforementioned self-piercing rivet, the self-piercing rivet having a rivet head and adjacent rivet shanks with two legs, wherein the legs extend inward or outward in the self-piercing riveting joint. The legs extend outward or inward relative to the longitudinal axis of the self-piercing rivet. Various design options for the self-piercing rivet allow for the formation of a stable joint. Furthermore, joints can also be formed where only a small amount of material can move or where it would be disadvantageous to have the self-piercing rivet protrude from the connected structural components.

[0021] The two components are preferably two components having at least flat connecting surfaces, abutting each other on the connecting surfaces, and both components are preferably metal sheets, particularly preferably metal sheets from a vehicle body. Referring to preferred embodiments of self-piercing rivets and their advantages, they are also applicable to self-piercing riveted joints. When a self-piercing rivet is used to connect two components, it is advantageous if the self-piercing rivet only at least partially penetrates the first structural component. However, it can also be configured such that the self-piercing rivet at least partially penetrates both the first and second structural components. In another design, where the self-piercing rivet is used to connect multiple components, it may be advantageous if the self-piercing rivet does not penetrate the last component furthest from the point of penetration. Attached Figure Description

[0022] The present invention will now be explained in more detail with reference to the embodiments shown in the accompanying drawings. The drawings show:

[0023] Figure 1 This is a top view of the self-piercing rivet design.

[0024] Figure 2 This is a perspective view of a self-piercing rivet design.

[0025] Figure 3 This is a top view of a self-piercing rivet design with countersunk heads.

[0026] Figure 4 This is a top view of a self-piercing rivet design with recesses in the side surface.

[0027] Figure 5 This is a side view of a self-piercing rivet design with recesses on the front and rear sides.

[0028] Figure 6 This is a side view of another embodiment of a self-piercing rivet having recessed grooves on the front and rear sides.

[0029] Figure 7 This is a front view of a self-piercing rivet design with a structured pattern on the front side.

[0030] Figure 8 This is a front view of a self-piercing rivet design with structural features on the rod leg.

[0031] Figure 9 This is a front view of a self-piercing rivet design with a wedge-shaped tip on the inside.

[0032] Figure 10 This is a front view of a self-piercing rivet design with structural features on the inner side of the recess.

[0033] Figure 11 This is a front view of a self-piercing rivet design with a wedge-shaped tip on the outside.

[0034] Figure 12 It is a front view of a self-piercing rivet design with structured features on the side surface of the rod leg, and

[0035] Figures 13 to 15 The method steps for attaching the strut to the structural component are illustrated schematically. Detailed Implementation

[0036] Figure 1 A top view of one embodiment of a self-piercing rivet is shown, and Figure 2 A perspective view of another embodiment of the self-piercing rivet is shown. The self-piercing rivet 1 can have a rectangular basic shape, which has opposing long sides and opposing narrow sides. Of course, a square basic shape is also possible. In another embodiment, the self-piercing rivet can have a trapezoidal shape. The basic shape refers to... Figure 1 A one-dimensional view of the self-piercing rivet 1 shown.

[0037] A rivet head 2 is provided at the first end of the self-piercing rivet 1, and a rivet shank 3 extends from the rivet head in the form of two legs 4 along the axial direction about the longitudinal axis of the self-piercing rivet 1 to the second free end of the self-piercing rivet 1. The rivet head 2 has a rectangular bridge-like or yoke-like design and connects the two legs 4. The outer corners of the rivet head 2 can be rounded.

[0038] The shank 4 is arranged perpendicular to the rivet head 2, i.e., perpendicular to the longitudinal axis of the rivet head, which extends transversely to the longitudinal axis of the self-piercing rivet 1. In the illustrated embodiment, the outer surface 5 of the shank 4, together with the side surface 6 of the rivet head 2, forms the longitudinal side of the self-piercing rivet 1. The side surface 5 of the rivet shank 3 is seamlessly integrated with the side surface 6 of the rivet head 2, so that the rivet head 2 and the rivet shank 3 preferably have a width W. This means that the width W of the self-piercing rivet 1 preferably remains constant along the length of the self-piercing rivet 1 in its undeployed state. In one embodiment, the side surfaces 5 and 6 (particularly the longitudinal side) of the self-piercing rivet 1 can be arranged parallel to each other. However, it may also be advantageous if the side surfaces 5 and 6 are not parallel to each other.

[0039] The shank 4 is laterally defined by a recess 7, which extends axially along the entire length L of the rivet shank 3 from the rivet head 2 along the central axis of the self-piercing rivet 1 and leads to an opening 8 opposite the rivet head 2. In the illustrated embodiment, the recess 7 extends radially relative to the central axis and widens continuously from the rivet head 2 to the opening 8. However, a substantially straight connection between the shanks 4 is also possible. In principle, the opening 8 is arranged on the narrow side of the self-piercing rivet 1. The upper end of the recess 7 adjacent to the rivet head 2 can be designed in different ways, for example, it can be rounded. For the purposes of this invention, radial specifically refers to the direction outward or inward relative to the longitudinal central axis of the self-piercing rivet. In other words, the shank is inclined toward or away from the central axis.

[0040] The leg 4 has its maximum width near the rivet head 2, and the leg 4 tapers axially toward its free end along the longitudinal axis of the self-piercing rivet 1. However, at least in the illustrated embodiment, the outer surfaces 5 of the legs 4 remain parallel to each other. Only the inner surfaces of the legs 4 extend toward their free ends in straight sections curving toward the outer surfaces 5. Therefore, the legs 4 have their minimum width at their free ends. The free ends of the legs 4 extend radially relative to the longitudinal axis of the self-piercing rivet 1 in certain regions, but do not extend beyond the side surfaces 5 of the legs 4. In the illustrated embodiment, the legs 4 are mirror-symmetrical about the central axis of the self-piercing rivet 1, which extends axially about the longitudinal axis.

[0041] The free end of the leg 4 or rivet 3 forms the leg base 9, which may be designed at least partially as a flat, recessed, convex or tapered surface.

[0042] The self-piercing rivet 1 is preferably made of metal and can be formed by stamping or laser cutting (or any similar technique) from sheet metal, metal strip (coil), or rolled metal strip. The self-piercing rivet 1 can also be manufactured using extrusion, rolling, or wire drawing processes. The self-piercing rivet 1 can also be made of stainless steel or tempered steel, such as 37MnB4 or similar (hardenable) materials. Alternatively, a soft metal (e.g., a soft metal coil) can be used for the self-piercing rivet 1 and subsequently hardened.

[0043] As shown in the figure, the self-piercing rivet 1 has a thickness or height h that remains constant along its length L and width W, particularly its height relative to its longitudinal extent along the longitudinal axis and its transverse extent to the longitudinal axis. This means that cost-effective manufacturing processes, such as stamping or cutting from sheet metal, can be used. This advantageous manufacturing method allows for easy modification of the profile or surface of the self-piercing rivet 1 through structural features, thereby affecting not only its insertion into the structural component but also its flow behind the component. Therefore, the installation behavior of the self-piercing rivet 1 and the resulting joint can be positively influenced through simple measures.

[0044] Figures 3 to 8 Various embodiments of a self-piercing rivet 1 are shown. The self-piercing rivet 1 may have a flange 10 on its rivet head 2. The flange 10 may be designed as a countersunk head that tapers from the side surface 6 of the rivet head 2. Furthermore, the self-piercing rivet 1 may have structural features such as grooves, notches 13, and / or ridges on at least one of its surfaces, for example, on... Figure 4 , Figure 5 and Figure 6 The side surfaces 5, 6, front side 11, and / or rear side 12 of the self-piercing rivet 1 are shown as an example. This structural variation in the surface profile can be provided in a simple manner during the manufacture of the self-piercing rivet 1 and supports the installation of the self-piercing rivet 1 or the underflow of structural components. This can also affect the deployment of the self-piercing rivet 1. By using structural features, a more stable connection of structural components can be provided. Additionally, for example... Figure 5 The imprint shown can be used to create the flange 10 and the notch or groove 13. In principle, an undercut structure can also be achieved. In addition, the side surface can be designed with tapered edges to make it easier for the self-piercing rivet 1 to penetrate the structural component.

[0045] The stability of the self-piercing rivet 1 may be affected by structural features such as the beads 14 or corrugations applied or introduced to the front side 11 and / or the rear side 12, which in turn affect the deployment and installation of the self-piercing rivet 1. Figure 8Structural features such as the recess 15 in the leg 4, and especially the surface 21 surrounding the recess, are shown. These structural features also affect the flow behind the structural components to be connected and the stability of the joint. The surface of the rivet head 22 can also be structured. Modifying at least one surface 5, 6, 11, 12, 21, 22 of the self-piercing rivet 1, at least partially by structuring, can improve the stability of the connection or joint. In this respect, it should be noted that the construction (especially the structural features) of the self-piercing rivet 1 can be combined with each other depending on the application of the self-piercing rivet 1.

[0046] Figures 9 to 12 Other embodiments of the present invention are shown. Figure 9 and Figure 10 An example of a variation is shown, in which the leg base 9 has a wedge-shaped end 23 substantially near the opening 8 and near the recess 7. In contrast, Figure 11 and Figure 12 The design of the wedge-shaped end 23, substantially close to the side surface 5 of the leg 4, is shown. The geometry of the leg 4 (particularly the geometry of the leg tip 20) affects the unfolding behavior of the self-piercing rivet 1. If the wedge-shaped end 23 of the leg base 9 is substantially close to the opening 8, the leg 4 tends to unfold towards the longitudinal central axis of the self-piercing rivet 1. In contrast, the geometry of the wedge-shaped end 23 of the leg base 9, substantially close to the side surface 5 of the leg 4, tends to favor the outward unfolding of the leg 4 relative to its longitudinally extending central axis.

[0047] Figure 10 The design of the inner surface 21 of the recess 7 having structural features such as notches or recesses 15 is also shown. Figure 12 A similar design is shown, in which the structural feature takes the form of a recess 15 or notch on the side surface 5 of the leg 4 near the rivet head 2. This structural feature can facilitate material flow around the rivet and result in a stable joint. This is particularly advantageous for thin parts.

[0048] The wedge-shaped end 23 is specifically created by a leg including at least one surface 24 inclined toward the longitudinal axis. According to an embodiment of the invention, the inclined surface 24 may be arranged near the side surface 5 of the leg 4 or near the recess 7. In one embodiment of the invention, see, for example, [reference needed]. Figure 9 The side surfaces 5 and 21 can advantageously extend parallel, at least in some sections. For example... Figure 11In another embodiment of the present invention shown, the leg 4, in addition to having the first inclined surface 24 described above, also has a second surface 25 inclined relative to the longitudinal axis, wherein the first inclined surface 24 forming the wedge-shaped end 23 extends more steeply than the second inclined surface 25. That is, in this embodiment, the first surface 24 and the second surface 25 do not have the same angle of inclination relative to the longitudinal axis. The transition portion between surfaces 24 and 25 may be curved. The wedge-shaped end 23 is specifically formed by the bevel of the leg base 9 of the self-piercing rivet 1, forming from the leg base 9 toward the side surface 5 or toward the side surface 20 of the recess 7.

[0049] The following will be done by using Figures 13 to 15 The following example illustrates the installation of the self-piercing rivet 1. For simplicity, only one leg 4 is shown. The self-piercing rivet 1 is installed using an installation tool shown only schematically. The installation tool essentially consists of a punch and a hold-down device 16.

[0050] The design of the self-piercing rivet 1 according to this invention allows for simple and cost-effective storage of the self-piercing rivet 1 in or on an installation tool. The structural components to be connected (i.e., the first component 17 and the second component 18) are formed flat at least on their connecting surfaces, such that components 17 and 18 abut against each other. Structural components 17 and 18 can be designed as sheet metal or body parts. The second structural component 18 rests on a mold serving as a reaction retainer 19. The installation tool approaches the connecting surface of the first structural component 17 axially and uses a clamping device 16 to place the self-piercing rivet 1 on the connecting surface. A punch then presses the self-piercing rivet 1 into the predetermined connecting surface, such that the shank base 9 of the self-piercing rivet 1 is pressed into the first structural component 17. Those skilled in the art will understand that this requires a certain amount of force, which depends on the material used and can vary depending on the application and material. Advantageously, at least one connecting area of ​​components 17 and 18 is pretreated, for example, by heat treatment of the connecting area or connecting surface. This can be achieved, for example, by plasma, laser or induction treatment, and can reduce the intensity of the treated parts 17, 18 in the heat-affected zone.

[0051] The self-piercing rivet 1 unfolds due to its geometry and the mold profile. The mold forms a reaction retainer 19 for the punch. In one embodiment, during uninterrupted connection, the self-piercing rivet 1 at least partially cuts through the upper structural member 17, and simultaneously, while expanding, plastically deforms the lower structural member 18 to form a closed head, the shape of which is substantially determined by the shape of the mold engraving. Variations that completely cut through the upper member 17 are also conceivable. In one embodiment, a mold without engraving can be used (thus essentially functioning as a flat block or anvil, primarily serving as a support).

[0052] The size (i.e., dimensions) of the self-piercing rivet 1 can be adapted to the application. In the illustrated embodiment, the leg 4 inserts into the second structural member 18 but does not protrude through it. One section of the leg 4 is substantially located in the first structural member 17, while another section is located in the second structural member 18. The installation process is completed upon contact or after anticipated movement following contact. In one embodiment, the installation process is completed when the rivet head 2 or flange of the self-piercing rivet 1 is substantially in contact with the first structural member 17. In another embodiment, the rivet head 2 may be pressed deeper into the upper structural member 17.

[0053] Structural components 17 and 18 are connected together. In the illustrated embodiment, the leg base 9 does not protrude from the second structural component 18. This seals the finished workpiece against damage from air and water and protects its appearance. However, it may also be advantageous if the leg bases 9 of the two legs 4 protrude completely through the second structural component 18. In another embodiment, the legs 4 can be configured to have different degrees of extension.

[0054] The main advantages of the self-piercing rivet 1 are its manufacturing process and compact design. The self-piercing rivet 1 can be stamped from sheet metal at low cost, thereby allowing for the introduction of contours such as embossed protrusions. Furthermore, materials that cannot be cold-formed, such as, but not limited to, stainless steel, can be used. This design eliminates the need for coating. Hardened sheet metal can also be used as the material. The self-piercing rivet 1 can be stacked for storage, saving space. Another advantage of the self-piercing rivet 1 is the very small deformation of the materials to be joined. This allows for very small margins and can also handle materials with very limited ductility / formability. Additionally, the joining force required using the preferred self-piercing rivet 1 is significantly lower. Tests have shown that the force required to drive the self-piercing rivet 1 into the structural component is only half that required by self-piercing rivets known in the prior art. This means that only half the force is needed for joining using the self-piercing rivet 1. This has significant advantages such as lower energy consumption and smaller installation requirements.

[0055] The self-piercing rivet 1 also offers several other advantages.

[0056] The self-piercing rivet 1 allows for small flanges and margins.

[0057] The self-piercing rivet 1 can generate favorable tension conditions during connection, which helps to prevent material from cracking on the mold side.

[0058] In precision stamping processes, multiple self-piercing rivets, as described above, can be punched out in a single operation.

[0059] Self-piercing rivets can be manufactured using materials that are not suitable for cold forming.

[0060] Such rivets can also be made of stainless steel, thus eliminating the need for subsequent coating or hardening. Before the rivet is stamped out, the raw material for the self-piercing rivet 1 can first be treated by methods such as hardening.

[0061] During installation, the orientation of the rivets can be adjusted to select directional characteristics.

[0062] The self-piercing rivet 1 is suitable for hybrid joining that combines adhesive and mechanical connections because it enables only localized adhesive displacement, resulting in better adhesive bonding with improved performance in the hybrid joining.

[0063] As mentioned above, the use of self-piercing rivets 1 requires lower connecting force, thus allowing for smaller drives and C-shaped frames compared to conventional rivets.

[0064] When using an anvil mold, there is no interference profile on the lower side, and the overall deformation of the connected parts is minimized.

Claims

1. A self-piercing rivet (1) for producing connecting joints, characterized in that, The self-piercing rivet (1) has a basic rectangular or trapezoidal shape and has a rivet head (2) and a rivet shank (3). The rivet shank includes two shank legs (4) spaced apart from each other and projecting perpendicularly from the rivet head (2) in one direction. The self-piercing rivet (1) has a recess (7) defined by the rivet head (2) and the shank legs (4). The opening (8) of the recess leads to a side opposite to the rivet head (2). The shank legs (4) taper in width from the rivet head (2) toward the shank leg base (9), but remain constant in height (h). The shank leg base (9) has a wedge-shaped end (23) arranged on the outside near the side surface (5) or near the recess (7). The shank legs (4) are adapted to extend inward or outward during connection.

2. The self-piercing rivet (1) according to claim 1, characterized in that, The self-piercing rivet (1) has a constant height relative to its longitudinal extent along the longitudinal axis and its transverse extent to the longitudinal axis.

3. The self-piercing rivet (1) according to claim 1, characterized in that, The range of the self-piercing rivet (1) in the height (h) direction is smaller than the range of the self-piercing rivet (1) in the length (L) and width (W) directions.

4. The self-piercing rivet (1) according to claim 1, characterized in that, A flange (10) is provided on the rivet head (2), the flange being designed as a countersunk or protruding head and protruding laterally beyond the rivet shank (3).

5. The self-piercing rivet (1) according to claim 1, characterized in that, At least one surface (5, 6, 11, 12, 21, 22) of the self-piercing rivet (1) has at least some structural features.

6. The self-piercing rivet (1) according to claim 1, characterized in that, The leg (4) is designed to be mirror-symmetrical with respect to the central axis of the self-piercing rivet (1), which extends axially with respect to the longitudinal axis of the self-piercing rivet.

7. The self-piercing rivet (1) according to claim 1, characterized in that, The recess (7) between the legs is rounded at the top in the direction toward the rivet head (2).

8. The self-piercing rivet (1) according to claim 1, characterized in that, The base of the leg (9) is at least partially designed as a flat, recessed, convex or tapered surface.

9. A self-piercing riveting joint, characterized in that, The self-piercing riveting joint has at least two structural components, including a first structural component (17) and a second structural component (18), which are connected to each other by a self-piercing rivet (1) according to any one of claims 1 to 8, the self-piercing rivet (1) having a rivet head (2) and an adjacent rivet shank (3) having two shank legs (4), wherein the shank legs (4) extend inward or outward in the self-piercing riveting joint.

10. The self-piercing riveting joint according to claim 9, characterized in that, The self-piercing rivet (1) penetrates only at least partially into the first structural component (17).

11. The self-piercing riveting joint according to claim 9, characterized in that, The self-piercing rivet (1) is at least partially inserted into the first structural component (17) and the second structural component (18).

Images