WO2004108325A1

WO2004108325A1 - Method for riveting two components using a blind rivet, and pre-mounted assembly unit of a blind rivet

Info

Publication number: WO2004108325A1
Application number: PCT/EP2004/006049
Authority: WO
Inventors: Klaus Dehlke
Original assignee: Richard Bergner Verbindungstechnik Gmbh & Co Kg
Priority date: 2003-06-05
Filing date: 2004-06-04
Publication date: 2004-12-16
Also published as: DE10325431A1; DE112004000952B4; DE112004000952A5

Abstract

According to the invention, two components (22A, B) are interconnected by means of a screw blind rivet (2) in a single-stage positioning process. To this end, said components are directly clamped between a collar (8) of a rivet sleeve (4) and a closing bulge (26), as for a conventional blind rivet connection. A rivet mandrel (4) embodied as a screw (6) is arranged in the rivet sleeve (4), engaging therewith by means of the thread thereof (20). In order to carry out said rivet connection, the screw (6) is first subjected to a translational pull and is then screwed tightly, and the thread (20) of the screw has a noncircular cross-sectional geometry in order to convert the applied torque as much as possible into a translational force component. Said thread (20) is alternately or simultaneously provided with flanks (32A, B) at different angles (α, ß), the angle (a) of the flank (32A) facing the screw head (16) being smaller than the angle (ß) of the flank (32B) opposing the screw head (16).

Description

Description Method for riveting two components with a blind rivet and pre-assembled

Assembly unit of a blind rivet

The invention relates to a method for riveting at least two components with a blind rivet, which comprises a rivet sleeve and a rivet mandrel remaining in the rivet sleeve, which is designed as a screw which engages with a thread in the rivet sleeve. During the setting process, the blind rivet is guided through a common bore of the components and then the sleeve material of the rivet sleeve is deformed into a closing bead in a deformation area, so that the components are clamped between the closing bead and a collar of the blind rivet. The invention further relates to a preassembled assembly unit of a blind rivet for use in such a method.

Such a method can be found in US 2,392,133. To form the closing bead, the screw is tightened in the known method. In this case, due to the engagement of the screw in the rivet sleeve, the latter is pulled in the direction of the screw head and thus against the components to be joined, so that sleeve deformation takes place and the closing bead is formed.

In contrast to the blind rivet to be found in US 2,392,133, the blind rivets used on the market today have a thread-free rivet mandrel. Such a blind rivet can be found, for example, in WO 00/68583. During the setting process, this blind rivet is inserted into the common hole until the blind rivet with its setting head comes to rest on the upper component. The mandrel guided through the rivet sleeve is supported with a mandrel head on the rear end of the rivet sleeve facing away from the setting head. When setting the rivet, the rivet mandrel is pulled with the aid of a setting tool supported on the component or on the setting head, so that the rivet sleeve is deformed and a closing bead is formed, and the components to be connected are clamped between the closing bead and the setting head. When a predetermined tensile force is reached, the mandrel preferably tears off flush with the setting head. Such a rivet connection, as can be seen, for example, from WO 00/68583, is used in various areas of technology, including in the automotive industry. When blind rivets are used to join body components in a motor vehicle, the body disadvantageously forms a type of resonance body. The vibrations generated by the tearing off are in fact transmitted to the body and amplified many times over, so that considerable noise pollution occurs. This noise level can reach values of up to 100db. Without special soundproofing measures, blind rivet technology cannot be easily integrated into an assembly line process. Furthermore, the disposal of the torn off residual mandrel is complex. The blind rivet is usually set manually with the aid of a hydraulically actuated setting tool designed in the manner of a pistol. Process monitoring is difficult due to the essentially manual setting.

In addition to the binding rivets, so-called blind rivet nuts are known which are inserted in the manner of a rivet into a bore in a component and have an internal thread into which a screw can subsequently be screwed for fastening a further component. In some cases, setscrews are screwed into the blind rivet nuts, to which other components can then be attached using conventional nuts. Such blind rivet nuts can be found, for example, in DE 692 13263 T2 or DE 201 12 171 U1.

According to DE 201 12 171 U1, the blind rivet nut is first inserted into a bore in a first component and is supported on it with a collar. In a second step, a further component is placed over it, which is attached using a

Screw that engages in the blind rivet nut is attached to the first component. When the screw is tightened, the rivet sleeve deforms so that a closing bead is formed on the underside of the lower component. At the same time, the rivet sleeve is pulled slightly upwards against the second component from the lower component.

However, the connection using the blind rivet nuts is complex in comparison to the conventional blind rivet setting process, since it requires a two-stage procedure, namely firstly inserting the blind rivet nut into the first component and Then, in the second stage, the second component is screwed on using a screw to be screwed into the blind rivet nut.

The invention has for its object to ensure a reliable formation of a blind rivet connection.

The object is achieved according to the invention by the method for riveting at least two components with a blind rivet according to claim 1. It is provided that the blind rivet, also referred to below as a blind rivet, has a rivet mandrel designed as a screw, which has a thread in the rivet sleeve intervenes. During the setting process, a setting tool grips the screw to form the closing bead and first pulls it translationally in the longitudinal direction, so that the closing bead is at least partially formed due to the purely translational movement. The screw is then tightened by rotating it. This setting process is therefore composed of a translatory and a rotary movement. During the translatory movement - like in a conventional setting process - the screw is gripped behind the screw head by the setting tool and pulled in the axial direction. The setting tool is supported in particular on a collar of the rivet sleeve.

In this case, the forming forces are preferably applied completely or almost completely by the translatory pulling, so that after the translational pulling the closing bead is completely or at least largely formed.

A particular advantage of this combined setting process can be seen in the fact that the high forming forces required for the forming of the rivet sleeve are at least largely applied by the simple, translational pulling movement. By subsequently tightening the screw, the necessary pre-tension is finally applied to hold the two components securely together.

The forces necessary for the forming are therefore not, or at least only partially, when the screw is tightened on the thread on the rivet sleeve transfer. A single reshaping with the screwing in of the screw would require a very high torque, over which, in addition to the necessary deforming force, a considerable friction between the thread of the screw and a corresponding thread area of the rivet sleeve would also have to be overcome. Radial expansion of the rivet sleeve, caused by the screwing movement, is also avoided by the combined setting process. Because due to the necessarily oblique configuration of the flanks of the thread of the screw, the force transmitted from the screw to the rivet sleeve has a component in the radial direction. When the screw is screwed in, the rivet sleeve will therefore endeavor to move radially outwards. The higher, the higher that of

Forces to be transmitted. Under certain circumstances, this can lead to the screw thread only being partially engaged with the threaded area of the rivet sleeve, so that the blind rivet connection yields in particular in long-term operation, for example under vibration stress. With the combination of translatory pulling provided here for the transmission of the necessary

Forming forces and the subsequent tightening of the screw to generate the necessary pretension overcome these problems in terms of a safe and reliable blind rivet connection.

Another advantage can be seen in the fact that this setting method combines the one-step setting process of a conventional blind rivet with the advantages of screwing technology in a particularly advantageous manner. During the setting process, the components to be connected are clamped between a collar of the rivet sleeve and the closing bead in only one work step. The screw has no direct contact with the components. The screw is not absolutely necessary to maintain the connection. Nevertheless, it preferably remains in the rivet sleeve in order to make the blind rivet connection more resistant in the manner of a locked residual mandrel. The screw is primarily used for forming the rivet sleeve during the setting process. The screw-type blind rivet is therefore largely independent of the component and is preferably a preassembled connecting element which, as such, is supplied to a particularly automatic processing station at which the screw-type blind rivet is inserted into the components to be connected. In comparison to the setting process of a conventional blind rivet, the advantages of screw blind rivets are that there is no tearing noise, that no residual mandrel has to be disposed of, and that existing tools can be used on the assembly line, for example in automobile production. In particular, this offers the possibility of using proven and established process monitoring systems for quality inspection.

The setting process of the blind rivet is expediently monitored automatically and this monitoring is in particular also recorded centrally. Since the setting process is ended with the aid of a screwing process, a torque monitoring which is customary in screwing technology can be used for this. The determined values are especially saved, evaluated and, if necessary, logged in order to enable complete and complete quality monitoring of each individual blind rivet connection. This is particularly desirable in the automotive sector with the high quality requirements.

The object is further achieved according to the invention by a preassembled assembly unit of a blind rivet according to claim 5. It is provided that the blind rivet has a rivet sleeve with a rivet mandrel formed therein. The screw already engages with a thread in the rivet sleeve, so that force can be introduced into the rivet sleeve during the setting process due to the translational pulling. The screw is designed in such a way that, when the screw is tightened, the greatest possible proportion of the force applied is converted into a translational component for any residual shaping that may still be necessary to form the closing bead and to generate the desired pretension. For this purpose, the screw thread has a non-circular cross-sectional geometry. Alternatively or in combination, a flank of the screw thread facing the screw head has a smaller flank angle than the flank facing away from the screw head.

The screw thread, which is non-circular at least in the partial area of the screw tip, is preferably provided with a trilobular cross-sectional area. Under out of round and in particular under trilobular one of the Understand a circular, deviating, non-circular cross-section, the outer circumference of which is composed of individual sections that do not run along a circular line. In this case, three shoulders are preferably formed, which are arranged rotatably offset from one another by 120 °. In particular, the non-round cross-sectional area has a uniform cross-sectional thickness, ie all lines running through the center have the same length. Due to the non-circular design, only a portion of the screw thread engages in the rivet sleeve and there is no full engagement. This measure keeps both the radial force component and the frictional force to be overcome low. In particular when using a thread-cutting or thread-forming screw, the so-called grooving torque, that is to say the torque to be applied for the formation of the thread turns, is kept low.

In view of the differently formed flank angles, the flank facing the screw head preferably has a flank angle in the range from approximately 10 ° to approximately 20 °, especially approximately 15 °. In contrast, the flank angle of the flank facing away from the screw head is approximately in the range from 35 ° to 45 °, especially 40 °. This measure at least largely prevents undesired widening of the rivet sleeve and, in addition, a screw of this type can be used to generate a large pre-tension during the setting process. These advantages are achieved due to the comparatively flat flank angle of the flank oriented towards the screw head. Due to this flat design, a large part of the applied torque is converted into a translational force component. The different flank angles also have a favorable effect on the friction forces that occur, so that the torsional load, in particular of the rivet sleeve, is low during the setting process.

The thread expediently tapers towards the thread tip. Preferably, the rivet sleeve 4 also tapers towards its end. This double taper turns radial when the screw is screwed in

Widening of the rivet sleeve effectively counteracted. The torque applied is thus largely converted into a translational force component, so that the highest possible amount of the applied torque is available for the forming process or for generating the prestress.

The screw is expediently designed as a thread-forming screw. In contrast to metric threads, this means that no further security measure against unintentional loosening of the screw is necessary. The screw thread is therefore largely free of play or completely free of play in the threaded area of the rivet sleeve.

To form the threaded area of the rivet sleeve, the procedure is preferably such that the screw is first inserted into the rivet sleeve and then the rivet sleeve is pressed into the screw thread in the threaded area, so that a thread is formed in the inner wall of the rivet sleeve. The screw is thereby secured in the rivet sleeve against falling out. The pressing is preferably carried out using a rolling process. As an alternative to this, the sleeve is crimped onto the thread by pressing the segmented press elements radially against the sleeve.

In order to ensure the best possible mechanical stability of the connection, in particular even in the case of shear stress, an especially thread-free collar below the screw head is adapted to the inside diameter of the rivet sleeve in an advantageous embodiment. The screw therefore has a thickened collar in the so-called clamping area, in which the components to be connected are clamped. The outside diameter of the collar corresponds in particular to the outside diameter of the thread adjoining the collar. The thread-free collar is designed such that when the screw is screwed into the rivet sleeve, the collar penetrates into the rivet sleeve without deformation.

The screw head in the assembly unit is expediently spaced from the rivet sleeve in the preassembled position before the setting process, so that the setting tool can easily reach behind the screw head. After completion of the setting process, the screw head is supported on the rivet sleeve. No component is therefore clamped between the rivet sleeve and the screw head. In order to enable the screw to be tightened, the rivet sleeve is preferably held in the bore so that it cannot rotate. For this purpose, in the region close to the collar, that is to say in particular in the clamping region in which the rivet sleeve is in engagement with the components, it has a cross-sectional shape which is form-fitting and in particular non-circular with the components. Alternatively or additionally, the collar is provided with counteracting surfaces for a tool, for example a wrench.

According to an expedient development, the rivet sleeve is closed at the end in particular in a gas-tight and liquid-tight manner. This enables an overall hermetically sealed connection arrangement, so that this connection arrangement is also suitable for those cases in which the rivet sleeve extends into a gas space with, for example, reactive gas. Since the rivet sleeve is closed at the end, there is no danger that the gas will penetrate into the rivet sleeve and possibly lead to a weakening of the rivet connection.

According to an expedient development, the rivet sleeve has a deformation region for the formation of the closing bead, the strength of which changes in the direction of the longitudinal expansion of the rivet sleeve. In particular, the strength in the deformation area decreases steadily towards the collar. This enables safe and reliable clamping even of different component thicknesses. The clamping range provided by the blind rivet is therefore variable.

In order to keep the load on the collar of the rivet sleeve as low as possible when the screw is tightened, a slide washer is arranged between the screw head and the rivet sleeve in a preferred development.

Exemplary embodiments of the invention are explained in more detail below with reference to the drawing. Each shows in schematic representations:

Fig. 1 is an illustration of a screw rivet referred to below

Blind rivet assembly unit when not in place, Fig. 2 is a blind rivet connection with two connected to the screw blind rivet

3A, B, C representations to illustrate the formation of the threaded portion of the

Rivet sleeve, Fig. 4 shows an embodiment variant of the screw blind rivet with a sliding washer and a closed rivet sleeve, Fig. 5A, B embodiment variants with an increased wall thickness of the rivet sleeve in

6A, B variants with a widened collar of the screw, Fig. 7A-D variants with different geometries for a non-rotatable arrangement of the rivet sleeve in the components, Fig. 8 a screw with different flank angles and

9A, B a thread-forming screw in a cross-sectional or

Side view.

1, the blind blind rivet 2 comprises a rivet sleeve 4, in which a rivet mandrel designed as a screw 6 is inserted. The rivet sleeve 4 has at its one end an approximately annular collar 8 and then a clamping area 10, a deformation area 12 and a thread area 14. The screw 6 comprises a semicircular screw head 16 and a screw shaft which is formed by a thread-free collar 18 and an adjoining shaft part with a thread 20. The thread 20 is in engagement with the rivet sleeve 4 in the threaded region 14, i.e. threads 14 are formed in the sleeve material in the threaded area 14. The rivet sleeve 4 has an increased wall thickness in the threaded region 14. Namely, a material step is arranged on the inner surface of the rivet sleeve 4 in the transition from the deformation area 12 to the thread area 14.

The screw head 16 is designed as a flat head with an approximately lenticular cross-sectional geometry with a tool holder, which is provided in particular for an internal hexagon force attack with an internal socket wrench. The screw head 16 has a significantly larger diameter than the rivet sleeve 4 on its underside, so that the screw head 16 has this largely covered. The overlap on both sides of the screw longitudinal axis is preferably about half the radius of the screw head on its underside, as can be seen for example from FIGS. 1 and 2. The large head contact surface enables high surface pressure. Through the design as a flat head, a low overall height is also achieved, so that only a small overall space is required. According to the exemplary embodiments, the screw head 16 is also designed as a combination screw head with an integrally formed washer, which forms the underside of the screw head.

The screw head 16 is spaced with its underside from the top of the collar 8. In this embodiment, the screw blind rivet 2 is fed as a preassembled unit to a blind rivet setting device.

When connecting two or more components 22A.B, the blind screw rivet 2, i.e. the preassembled unit consisting of the rivet sleeve 4 and the screw 6 screwed into it, is first inserted through a common bore in the components 22A, B until it engages the collar 8 comes to rest on the top of the upper component 22A. The collar 8 is in this case seen on its underside in cross section slightly S-shaped and not flat, so that it comes to rest flatly only with its outer edge region on the upper component 22A, including an annular space 24.

To form the closing bead, the screw head 16 is first gripped by a setting tool (not shown here) and pulled in the longitudinal direction of the rivet sleeve 4 and counter to the setting direction in the direction of arrow 27A. The setting tool is preferably supported on the collar 8. The rivet sleeve 4 is compressed by the engagement of the thread 20 in the thread region 14 in the sleeve material of the rivet sleeve 4 and by the translational movement along the arrow 27A. The closing bead 26 forms in the forming area 12. The strength in the deformation region preferably decreases steadily in the direction of the collar 8. This ensures that different component thicknesses can be handled without any problems. Because of the decreasing strength towards the collar 8, the closing bead 26 is initially in the areas of lower strength and thus always in in the immediate vicinity of the surface of the lower member 22B. The different strength values of the rivet sleeve are achieved with a constant wall thickness, for example by a defined heat treatment, in particular an area-by-area annealing with a defined cooling.

Following this translational movement along the arrow 27A, that is to say in particular after the end of the sleeve shaping, the screw 6 is screwed in until the screw head 16 lies flush on the collar 8. By screwing in and tightening the screw 6 to a predetermined torque, it is held firmly in the rivet sleeve 4 and the pretension is secured. The setting process is therefore composed of a translatory (arrow 27A) and a rotary component (arrow 27B). These two movements take place immediately one after the other. By pulling the setting tool on the screw head 16, very high tensile forces and thus very high forming forces can be used to fold the sleeve. A particular advantage of the setting process can be seen in the fact that it takes place in one step, in the sense that the blind blind rivet 2 is only passed through the common bore of the two components 22A, 22B and these are then riveted together only by actuating the screw 6.

To carry out the setting process, a uniform combination setting tool is preferably used, with which both the translational and the rotary movement are used. An adapted screwing tool is used here in particular as a setting tool. Such screwdrivers are usually already designed with an axial feed function for the automatic feeding of a screw. This feed function is expediently used in a modified form for the translatory pulling of the screw 6 of the screw blind rivet 2.

In the case of the blind rivet connection with the screw blind rivet 2, the components 22A, B are clamped directly between the collar 8 and the closing bead 26. After the setting process, the screw 6 remains as a residual mandrel in the rivet sleeve 4, as in the case of a conventional blind rivet. This makes it durable and highly stressable Blind rivet connection formed. The connection with the screw-type blind rivet 2 has the essential advantages that the rivet mandrel does not tear off, that no residual mandrel is disposed of and that in particular simple automatic monitoring, in particular torque monitoring, is possible. Another decisive advantage is that the simple one-step setting process of a conventional blind rivet is retained, so that the two components 22A.B can be connected to one another in a single step. As with a conventional blind rivet, the screw-type blind rivet 2 is in particular also automatically fed to the preferably combined pulling and screwing tool. This is simply placed on the common bore of the components 20A.B to be connected, in order to connect them by pulling and turning the screw 2 in a single step.

With regard to the most economical and simple design of the screw blind rivet 2, the threaded region 14 is formed in that the

Screw 6 is first inserted into a hollow cylindrical rivet shaft of the rivet sleeve 4. The end of the sleeve shaft in the threaded region 14 is then pressed against the thread 20 of the screw 6 by a rolling process. Here, 14 threads are formed in the sleeve material of the rivet sleeve 4 in the threaded region (FIG. 3A.3B). Instead of a rolling process, the end of the sleeve shaft is alternatively deformed by radially pressing two or more pressing segments 29. In the exemplary embodiment in FIG. 3C, a total of four pressure segments 29 are shown over the circumference of the rivet sleeve 4 which is not round in this variant, which are each moved in the direction of the arrow on the rivet sleeve 4 and press or squeeze it against the thread 20. In this top view according to FIG. 3C, the receptacle for an internal wrench can also be seen very well.

In order to bring the thread 20 into engagement with the sleeve material, according to an alternative variant, a thread is cut into the sleeve material, in particular with the aid of a thread-cutting screw 6. This is preferably done during the pre-assembly of the screw blind rivet 2. 4, a sliding washer 28 is provided between the screw head 16 and the collar 8. This reduces the frictional forces transmitted from the screw head 16 to the collar 8 when the screw 6 is tightened. Furthermore, an embodiment variant with a closed rivet sleeve 4 is shown in FIG. 4, which is approximately pot-shaped with a lower base 30. In this embodiment variant with the closed rivet sleeve 4, the screw 6 therefore does not come into contact with the surroundings below the lower component 22B. The screw 6 is hermetically sealed.

According to the further embodiment variants according to FIGS. 5A and 5B, the rivet sleeve 4 has an increased wall thickness in the threaded region 14, a shoulder being formed on the inside of the rivet sleeve 4. The initially hollow cylindrical rivet sleeve 4 (FIG. 5A) is converted into a conical shape by the rolling process described for FIG. 3B, so that the thread 20 in the threaded region 14 is pressed into the rivet sleeve 4 with the increased wall thickness. In this embodiment variant, the outer cross section of the rivet sleeve 4 in the region of the rivet shaft towards the collar 8 increases continuously.

In the embodiment variant according to FIGS. 6A.6B, in addition to the increased wall thickness in the threaded region 14, the collar 18 is widened. The

The outer diameter of the collar 18 corresponds approximately to the outer diameter of the thread 20 and the collar 18 lies approximately flush in the rivet sleeve 4. Here, too, the thread 20 is pressed into the sleeve material in the threaded region 14 by the rolling process. Because of the wide collar 18, the rivet sleeve 4 now has a continuously widening conical configuration in the lower region and a cylindrical configuration in the region of the collar 18.

As can be seen from FIGS. 7A to 7D, the rivet sleeve 4 in the clamping area 10 below the collar 8 has a non-circular cross-sectional geometry, for example an elliptical geometry (FIG. 7A), a geometry with flattened sides (FIG. 7B) or a polygonal, especially hexagonal geometry (Fig. 7C). Because of this geometry, the rivet sleeve 4 lies in a form-fitting manner in the components 22 to be connected and is thus held against rotation in the components 22, so that a problem-free one Tightening torque can be exerted without the rivet sleeve 4 also rotating. The form-fitting seat of the rivet sleeve 4 is achieved, for example, by pressing and reshaping the initially circular hole in the components 22A.B.

In order to transmit the lowest possible twisting forces to the rivet sleeve 4 during the setting process, the thread 20 has a geometry which generates little friction, as can be seen in FIG. It is then provided that the flank angle α of a flank 32A facing the screw head 16 is smaller than the flank angle β of the second flank 32B facing away from the screw head 16. The flank angle α, β is formed by the angle which the respective flank 32A, B encloses to form a line which is perpendicular to the longitudinal axis of the screw. The flank angles, ß are approximately 15 ° or 45 ° according to the exemplary embodiment.

FIGS. 9A, 9B show a thread-forming screw 6, the thread 20 of which has a non-circular, in particular triolobular cross-sectional geometry with three shoulders 34, each offset by 120 ° (FIG. 9A). Furthermore, the outer circumference of the thread tapers towards the thread tip 36 in order to enable easy insertion. Due to the non-circular cross-sectional geometry, only a partial area of the thread 20 is in engagement with the sleeve material. Accordingly, the forces to be applied, that is to say the torque to be applied when the screw 6 is screwed in, in particular during thread grooving, are kept low. The thread is cut into the rivet sleeve 4 with the thread-forming screw 6. The thread-forming screw is also expediently used in the embodiment variant in which the threads are cut into the rivet sleeve by rolling or pressing on the rivet sleeve.

With regard to the goal of converting as much of the applied torque as possible into a translatory component in the direction of the longitudinal axis of the screw and not into a radial force component or to overcome frictional force when screwing in the screw, it is particularly advantageous that the height of the screw threads 6 towards the threaded tip 36. The rivet sleeve 4 expediently also tapers in its threaded region 14, as is shown, for example, in FIGS. 5B and 6B. Due to the double-conical design of both the thread 20 and the rivet sleeve 4, which thus both taper towards their end, the radial evasive movement of the rivet sleeve 4 is effectively counteracted when the screw is screwed in.

LIST OF REFERENCE NUMBERS

Schraubblindniet

rivet sleeve

screw

collar

clamping range

deformation zone

threaded portion

screw head

Federation

Thread A upper component B lower component

free space

arrow

Closing bead A.B arrow

sliding disk

Anpresssegment

Bottom A.B flanks

shoulder

threaded tip

ß flank angle

Claims

Expectations

1. Method for riveting at least two components (22A.B) with a blind rivet (2), which comprises a rivet sleeve (4) and a rivet mandrel remaining in the rivet sleeve (4), which is designed as a screw (6) which is provided with a thread (20) engages in the rivet sleeve (4), the blind rivet (2) being guided through a common bore in the components (22A.B) and then in a deformation region (12) the sleeve material of the rivet sleeve (4) forming a closing bead ( 26) is deformed so that the components (22 A, B) are clamped between the closing bead (26) and a collar (8) of the blind rivet (2), characterized in that for the formation of the closing bead (26) with the aid of a setting tool the screw (6) is first pulled translationally and then tightened by a rotational movement

2. The method according to claim 1, characterized in that after the translational pulling of the closing bead is at least largely completely formed.

3. The method according to any one of claims 1 and 2, characterized in that the setting process of the blind rivet (2) is automatically monitored and the monitoring is recorded in particular centrally.

Pre-assembled assembly unit of a blind rivet (2) with a rivet sleeve (4) and a rivet mandrel arranged therein, which is designed as a screw (6) with a screw head (16) which engages with a thread (20) in the rivet sleeve (4), characterized in that the screw thread (20) has a non-circular cross-sectional geometry and / or in that the screw thread (20) has a flank (32A) facing the screw head (16) and a flank facing away from the screw head (16) Flanks (32B), the flank (32A) facing the screw head having a smaller flank angle (α) than the flank facing away (32B).

5. Blind rivet (2) according to claim 4, characterized in that the screw thread (20) has a trilobular cross-sectional geometry.

6. Blind rivet (2) according to claim 4 or 5, characterized in that the flank (32A) facing the screw head has a smaller flank angle (α), in particular in the range from 10 ° to 20 °, especially 15 °, than that facing away from the screw head Flank (32B), the flank angle (ß) is in particular in the range of 35 ° - 45 °, especially at 40 °.

7. Blind rivet (2) according to one of claims 4 to 6, characterized in that the thread (20) tapers conically and / or that the rivet sleeve (4) tapers conically to its end opposite the collar (8).

8. Blind rivet (2) according to one of claims 4 to 7, characterized in that the screw is a thread-forming screw (6).

9. Blind rivet (2) according to one of claims 4 to 8, characterized in that the rivet sleeve (4) is pressed to form a threaded region (14) in the screw thread (20).

10. Blind rivet (2) according to one of claims 4 to 9, characterized in that the screw (6) below the screw head (16) has a thread-free collar (18) which is adapted to the inside diameter of the rivet sleeve (4).

11. Blind rivet (2) according to one of claims 4 to 10, characterized in that the screw head (16) of the screw (6) is spaced from the rivet sleeve in the preassembled position and is supported on the rivet sleeve (4) in the set state.

12. Blind rivet (2) according to one of claims 4 to 11, characterized in that the rivet sleeve (4) is held against rotation in the components (22 A, B).

13. Blind rivet (2) according to one of claims 4 to 12, characterized in that the rivet sleeve (4) is closed at the end.

14. Blind rivet (2) according to one of claims 4 to 13, characterized in that the rivet sleeve (4) has a deformation region (12), the strength of which in the direction of the collar (8) in particular steadily decreases.

15. Blind rivet (2) according to one of claims 4 to 14, characterized in that a sliding washer (28) is arranged between the screw head (16) and the rivet sleeve (4).