Patent Application
20230213055
Priority is claimed to German Patent Application No. DE 10 2022 100 104.0, filed Jan. 4, 2022. The entire disclosure of said application is incorporated by reference herein.
The present invention relates to the technical field of setting blind rivet nuts or blind rivet studs, wherein the blind rivet studs are also referred to as blind rivet screws. The present invention in particular relates to a blind rivet nut or to a blind rivet stud that enables a non-projecting setting into a clearance of a workpiece. The present invention also relates to a suitable blind rivet nut setting tool or blind rivet stud setting tool for setting such a blind rivet nut or such a blind rivet stud, to a method, and to an assembly system for setting the blind rivet nut.
Blind rivet nuts which, when the blind rivets are incorporated in a smooth bore of a workpiece via the countersunk head thereof, for example, upon setting have a projection, are known from the prior art. Such a blind rivet nut is described, for example, in DE 10 2013 214 247 A1. Such a projection, which configures an interfering edge on the workpiece, is undesirable for many applications.
The prior art describes successfully avoiding such an interfering edge when a corresponding countersinking about the bore in the workpiece is provided prior to setting the blind rivet nut, wherein the countersunk head of the blind rivet nut is completely incorporated in the countersinking.
This provision of countersinking is disadvantageous as an additional effort is always required, and is disadvantageous above all for reasons of stability in the case of thin workpieces.
An aspect of the present invention is to provide a blind rivet nut, a blind rivet nut setting tool for setting such a blind rivet nut, a method, and an assembly system for setting the blind rivet nut, so as to make a non-projecting or an almost non-projecting setting of the blind rivet nut possible, and to thereby at least partially eliminate the disadvantages of the prior art set forth above. An aspect of the present invention is also to provide a blind rivet stud, a blind rivet stud setting tool for setting such a blind rivet stud, a method, and an assembly system for setting the blind rivet stud, so as to make possible a non-projecting or an almost non-projecting setting of the blind rivet stud and to thereby at least partially eliminate the disadvantages of the prior set forth above.
In an embodiment, the present invention provides a blind rivet nut for incorporating a thread in a clearance of a workpiece and/or for connecting two workpieces. The blind rivet nut includes a setting region, a thread region which comprises an internal thread at least in portions of the thread region, and a compression region arranged between the thread region and the setting region. The compression region is configured so that, when a first force acting on the compression region is exceeded, the compression region forms a closing bead. The setting region comprises an axial portion which faces the compression region and a free axial portion which faces away from the compression region and from the thread region. The setting region, on the free axial portion which faces away from the thread region, is configured so that, with respect to an external dimension of the setting region, the setting region is enlarged at least in a radial direction when a second force acting on the setting region is exceeded.
The present invention is described in greater detail below on the basis of embodiments and of the drawings in which:
The present invention provides a blind rivet nut for incorporating a thread in a clearance of a workpiece and/or for connecting two workpieces, wherein the blind rivet nut comprises:
A core concept of the present invention is that the setting region on the free axial portion thereof facing away from the thread region, when a second force acting on the setting region is exceeded, in terms of the external dimensions thereof, is able to be enlarged at least in a radial direction. The first force and the second force can be caused by a single lifting movement of a blind rivet nut setting tool, and can in particular also be of substantially identical size. The first force and the second force would in this case be for all extents and purposes a “single force”.
The blind rivet nut according to the present invention differs from a blind rivet nut from the prior art substantially in that the blind rivet nut according to the present invention does not have a setting head which, when incorporated in a clearance of a smooth surface, causes an interfering edge, because the setting head via the interfering edge/setting head conventionally fixes the blind rivet nut in an axial direction on the surface. As a result of the free axial portion of the setting region, where the setting head is located in conventional blind rivet nuts, being able to be enlarged by exerting the force, the blind rivet nut upon complete incorporation in a clearance of a workpiece can thus be deformed so that a friction-fit and/or form-fit with the workpiece can be generated. The blind rivet nut can thereby be fixed axially on, or rather in, the workpiece in a non-projecting or in an almost non-projecting manner. The force here exerted should, for example, also be sufficiently high in order for the workpiece to be deformed because a form-fit generally offers better axial fixing than a friction-fit. The external dimensions of the blind rivet nut are smaller than the internal dimensions of the clearance so that the blind rivet nut can be incorporated in the clearance with a small amount of play. The clearance can, for example, be in the shape of a hole. The clearance can in particular be a bore. It is also generally possible for the first force and the second force to be of an identical size so that the closing bead as well as the deformation of the free axial portion can be generated as a result.
It is in principle sufficient for the enlargement to be generated along a single radial direction. The enlargement can, for example, be performed along a straight line. Stability is increased when the enlargement can, for example, be generated symmetrically along a plurality of directions, in particular when the free axial portion is enlarged in a circular manner. This circular enlargement in three-dimensional terms can, for example, correspond to a conical enlargement.
The blind rivet nut can, for example, be made of steel, high-grade steel, copper, copper alloy and/or aluminum. In an embodiment, the blind rivet nut is integrally configured to have a homogeneous material composition. This advantageously makes possible an efficient production of the blind rivet nut.
The present invention also provides a blind rivet stud for incorporating a thread in a clearance of a workpiece and/or for connecting two workpieces, wherein the blind rivet stud comprises:
The technical effects and advantages of such a blind rivet stud correspond to those that have been described above in the context of the blind rivet nut. The blind rivet stud may also be referred to as a blind rivet screw.
Such blind rivet studs according to the present invention, after setting, have a projection of 0 mm in the components or in the workpieces. Components or workpieces can thereby be screwed to one another completely without interfering edges.
As a result of the shape and embodiment of the sleeve of the blind rivet stud without a head of any dimensions, the sleeve, while utilizing a mouthpiece with an appendage, can be incorporated in a non-projecting manner in a component. The sleeve of the blind rivet stud can have different shapes (round, hexagonal, etc.); knurls, grooves, appendages, etc., in the shank region are also possible.
Advantageous design embodiments, in particular the technical effects thereof, will be described hereunder, in most instances in the context with the blind rivet nut. As is clear to the person skilled in the art, the technical effects likewise apply to the blind rivet stud according to the present invention.
In a design embodiment of the blind rivet nut, the portion of the setting region that faces away from the thread region can, for example, be substantially free of projections. In a design embodiment of the blind rivet stud, the portion of the setting region that faces away from the screw region can, for example, be substantially free of projections.
This has the advantage that the blind rivet nut can be readily incorporated in the clearance. Further advantages include the following: if the projection were located where the setting head is in conventional blind rivet nuts, the risk would exist that an interfering edge is again created when the setting region is being enlarged because the projection would be able to slide onto the surface of the workpiece when the radial force is being exerted. However, if the projection were disposed further in the direction of the thread region of the blind rivet nut, this would inevitably increase the spacing of the enlargeable setting region from the workpiece so that the setting region would disadvantageously have to be more intensely deformed. Comparatively small unevennesses caused by the material are not referred to as projections within the context of this text.
In a design embodiment of the present invention, an external shape of the blind rivet nut or of the blind rivet stud can, for example, be at least largely cylindrical; the external shape configuring in particular a straight extent parallel to a rotation axis in terms of an elongate extent of the blind rivet nut or of the blind rivet stud. A further possibility for describing the external shape of the blind rivet nut or of the blind rivet stud is that the external shape is configured like a sleeve.
This offers the advantage that the blind rivet nut is particularly easy to produce and, when incorporated in the clearance of the workpiece, has a uniform spacing from an internal region of the workpiece. In order to enable the blind rivet nut to be more easily incorporated in the workpiece, the free thread portion can be slightly bent in the direction of the longitudinal axis of the blind rivet nut. This bent region can, for example, not be longer than 10% of the length of the blind rivet nut. This makes it possible that the blind rivet nut can more easily be incorporated in the clearance, and that the blind rivet nut across the largest part of the longitudinal region thereof nevertheless has a uniform spacing from the internal region of the workpiece.
In a design embodiment of the present invention, the enlargement in the radial direction in terms of the external dimension can, for example, be more than 0.1%, for example, 0.5%, for example, 1%.
The choice as to the extent to which the external dimension is to be able to be enlarged will also depend on how high potential axial forces are in relation to which the blind rivet nut has to be able to be fixed. It moreover applies that the greater the enlargement, the more the ratio of friction-fit component to form-fit component shifts in the direction of the form-fit component. The smaller the enlargement, the less force must be exerted on the blind rivet nut when the latter is being incorporated. The blind rivet nut can accordingly also be more flexibly designed in terms of material technology. It has been demonstrated that an enlargement in terms of the external dimension of more than 0.1% is already sufficient for providing sufficient axial fixing of the blind rivet nut in a multiplicity of application fields. If a friction-fit is already sufficient in specific applications, the enlargement may also be less than 0.1%.
The first force and the second force can, for example, be of dissimilar sizes.
This makes it possible for the form-fit and/or the friction-fit to be generated also in cases where a higher force is required in order for the workpiece to be deformed than in order for the closing bead of the blind rivet nut to be generated. For this purpose, the blind rivet nut setting tool described in more detail hereunder can, for example, have two different modes, wherein the closing bead is generated via the first force using the first mode, and the setting region on the free axial portion is enlarged via the second force using the second mode.
In an embodiment, the thread region or the screw region can, for example, be configured from a high-tensile material, wherein the thread region or the screw region is not able to be deformed.
As opposed to conventional blind rivet nuts, the second force must be sufficient for deforming the free axial portion of the setting region as well as the workpiece. At the same time, however, the thread region should remain intact should the blind rivet nut in a later state also provide a thread in the clearance. These characteristics thus advantageously make it possible that the free axial portion of the setting region as well as the workpiece are deformed while at the same time the thread region remains intact. It is in principle possible in this context that the setting region and the thread region are produced using dissimilar materials, however, the setting region and the thread region can, for example, be produced from the same materials because this is more efficient in terms of production, wherein the setting region and the thread region in the production process are at least at times differently treated, as a result of which the thread region is more resistant, i.e., harder, in relation to deformations than the setting region. If the blind rivet nut is intended to only connect two workpieces to one another, which is also possible in principle, it is not mandatory for the thread region to remain intact.
The present invention also provides a blind rivet nut setting tool for setting the blind rivet nut described above, wherein the blind rivet nut setting tool comprises:
It is here a substantial feature that the mouthpiece has a detent portion for the blind rivet nut, wherein the detent portion has a detent face which decreases in size in the direction of the thread portion.
The detent portion of the mouthpiece here forms the counter bearing which is required in order for the blind rivet nut to be deformed when the thread pin, as a result of the lifting movement, is retracted through the mouthpiece. The setting region of the blind rivet nut is in this case pressed against the mouthpiece and can be deformed. The shape of the detent face according to the present invention makes it possible that the free axial setting region of the blind rivet nut described above is enlarged, and the closing bead of the blind rivet nut is also generated, potentially in an upstream or downstream process. The further the lifting module thus retracts the thread pin, the deeper the detent face is pressed into the free axial setting region of the blind rivet nut, thus enlarging the latter. As has been described above, a form-fit and/or friction-fit with the clearance of the workpiece is generated as a result of this enlarged free axial setting region. The threaded portion of the thread pin is, for example, typically designed as a counter thread to the internal thread of the blind rivet nut.
The present invention also provides a blind rivet stud setting tool for setting a blind rivet stud described above, wherein the blind rivet stud setting tool comprises:
The advantages and technical effects of the blind rivet stud setting tool correspond substantially to the blind rivet nut setting tool described above.
Advantageous design embodiments, in particular the technical effects thereof, will be described hereunder in most instances in the context of the blind rivet nut setting tool. As is clear to the person skilled in the art, the technical effects also apply to the blind rivet stud setting tool according to the present invention.
In an embodiment of the present invention, the detent face can, for example, be enlarged continuously or by way of different angles.
If the detent face is continuously enlarged, this has the advantage that the detent face is generally easier to produce, wherein a detent face having different angles is suitable for flexibly determining how high the force is that the detent face exerts on the blind rivet nut, depending on the retraction depth of the thread pin. The material of the detent face can, for example, be chosen so that the material is not deformed by the setting process. The material of the detent face should thus in particular be sufficiently large so as not to be deformed by the second force.
The detent face of the blind rivet nut setting tool can, for example, have a region facing the threaded portion that is smaller than an internal region of the free axial portion of the setting region of the blind rivet nut, and the detent face has a region facing away from the thread portion that can, for example, be larger than the internal region of the free axial portion of the setting region of the blind rivet nut.
It is advantageously made possible as a result that the detent face can be readily incorporated in the free axial portion of the setting region of the blind rivet nut, and enlarges the latter when the thread pin is continually retracted in the direction of the mouthpiece.
In a design embodiment of the present invention, the detent face can, for example, be configured to be conical.
Such a detent face is easy to produce and also advantageously leads to a uniform force being exerted on the blind rivet nut and thereby also indirectly on the workpiece. Such a uniform exertion of force is generally particularly efficient and likewise leads to uniform axial fixing. Such uniform characteristics are generally advantageous because predetermined breaking points or the like are thereby prevented.
The present invention also provides for a method for setting a blind rivet nut in a clearance of a workpiece while using the blind rivet nut described above and the blind rivet nut setting tool described above, the method comprising the following steps:
As a result of the free axial setting region being completely incorporated in the clearance of the workpiece, it is possible for the blind rivet nut to be set without an interfering edge on the corresponding surface of the workpiece being generated. This is made possible in that, upon complete incorporation, the axial fixing of the blind rivet nut is implemented by the form-fit and/or friction-fit, the latter being generated when the free axial setting region as a result of the enlargement local bearing stress is brought to bear on the workpiece.
The present invention also provides for a method for setting a blind rivet stud in a clearance of a workpiece while using a blind rivet stud described above and a blind rivet stud setting tool described above, the method comprising the following steps:
By using the mouthpiece having the appendage, thus the detent face, the shank of the sleeve of the blind rivet stud is pushed open outward in the setting process, and local bearing stress is brought to bear in the bore of the component. The contour of the appendage on the mouthpiece can here have different shapes. The blind rivet stud is pulled smoothly up to the upper side of the component as a result of the setting procedure. The closing bead is formed as in a standard blind rivet stud. The blind rivet stud is set in a non-projecting manner in the component and thus has a projection of 0 mm. No interfering edge is, for example, created. An additional process of “countersinking” the bore is not required as is the case, for example, in countersunk head embodiments of the blind rivet studs.
The present invention also provides for an assembly system for setting a blind rivet nut or a blind rivet stud, said assembly system comprising:
In a design embodiment, the assembly system can, for example, additionally comprise a workpiece having the clearance into which the blind rivet nut is incorporated as described in the method.
Exemplary embodiments of the present invention will be explained below under reference to the drawings.
Numerous features of the present invention will be explained in detail hereunder via embodiments. The present disclosure is thereby not limited to the combinations of features specifically mentioned. The features here mentioned can much rather be combined in an arbitrary manner so as to form embodiments according to the present invention unless expressly precluded hereunder.
The blind rivet nut setting tool 150 has a thread pin 155 which at least in portions, on the portion facing away from the blind rivet nut setting tool 150, has a thread (which is not shown). The thread pin 155 can, however, also be configured as a thread along the entire region thereof shown in
The mouthpiece 160 has a detent portion 165, wherein the detent portion 165 has a detent face 170 which decreases in size in the direction of the free end of the thread pin 155. This may also be worded so that the detent face by way of the larger face thereof faces the mouthpiece 160, and the smaller face thereof faces away from the mouthpiece 160. The detent portion 165 in particular has a conical shape, the larger face thereof bearing on the mouthpiece 160, or being able to be connected to the latter.
The blind rivet nut 105 in the lateral view displays the shape of a sleeve. The thread pin 155 can coaxially penetrate the blind rivet nut 105 and in particular engage in an internal thread (not shown in the lateral view) of the blind rivet nut 105, or spin on the internal thread, respectively.
The blind rivet nut 105 has a setting region 110, a compression region 115, and a thread region 120. The setting region 110, at least on the free axial portion 112 thereof facing away from the thread region 120, when a second force acting on the setting region 110 is exceeded, in terms of the external dimension thereof is able to be enlarged in the radial direction. To this end, the second force can in particular act in a radially outward manner. In principle, dimensions of the blind rivet nut 105 can be flexibly designed and accordingly be adapted so as to depend on the clearance of the workpiece. When the first force is being exerted, the compression region 115 is deformed so as to form a closing bead. The thread region 120 comprises the internal thread which is not shown in
Different shapes which the blind rivet nut 105 can assume include, for example, a round cross section or a hexagonal cross section in terms of the longitudinal axis 125 through the blind rivet nut 105. The external surface of the blind rivet nut 105 of the setting region 110 can have a fluting 111. The fluting 111 provides that the blind rivet nut 105 is secured in relation to the twisting in the clearance of the workpiece.
The corresponding deformations of the workpiece 200 and of the blind rivet nut 105 are illustrated enlarged in
The enlargement of the free axial portion 112 in the case of a conical contact face can also be described as follows. The free axial portion 112 in a state not impinged by a force has a radius R1, wherein the free axial portion 112 upon impingement by the force of the second force has a radius R2, where R1<R2.
As can be seen in
It also applies to the exemplary embodiments hereunder that the technical effects and advantages which are described above in the context of the blind rivet nut also apply to the blind rivet stud.
Accordingly, the blind rivet stud setting tool 150b has an internal thread 152 onto which a screw 155b of the blind rivet stud can be driven. The screw 155b runs coaxially through a mouthpiece 160b. The screw 155b can be axially displaced through the mouthpiece 160b, in particular by the lifting module (which is not shown).
The mouthpiece 160b has a detent portion 165b, wherein the detent portion 165b has a detent face 170b. The detent face 170b by way of the larger face thereof faces the mouthpiece 160b, and by way of the smaller face thereof faces away from the mouthpiece 160b. The detent portion 165b in particular has a conical shape, the larger face thereof bearing on the mouthpiece 160b, or being able to be connected to the latter.
The blind rivet stud 105b in the lateral view displays the shape of a sleeve. The screw 155b can coaxially penetrate the blind rivet stud 105b and in particular have an external thread not shown in the lateral view.
The blind rivet stud 105b has a setting region 110b, a compression region 115b, and a screw region 120b. The setting region 110b, at least on the free axial portion 112b thereof facing the screw region 120b, when a second force acting on the setting region 110b is exceeded, in terms of the external dimension thereof, is able to be enlarged in the radial direction. To this end, the second force can in particular act in a radially outward manner. In principle, dimensions of the blind rivet stud 105b can be flexibly designed and accordingly be adapted so as to depend on the clearance of the workpiece 200. The compression region 115b is deformed so as to form a closing bead when the first force is being exerted. The screw 155b is fixed in the screw region 120b and can exert a corresponding force on the compression region 115b so that a closing bead is formed. The screw region 120b on the free end thereof has a conically tapered region 121. The conically tapered region 121 makes it possible that the blind rivet stud 105b can be more easily incorporated in a clearance of the workpiece 200. Self-centering of the blind rivet stud 105b in the clearance of the workpiece can be initiated by the conically tapered region 121. The compression region 115 should extend into the knurled region of the setting region to the extent of approximately ⅓.
Different shapes which the blind rivet stud 105b can assume include, for example, a round cross section or a hexagonal cross section. The external surface of the blind rivet stud 105b of the setting region 110 can have a fluting 111. The fluting 111 provides that the blind rivet stud 105b is secured in relation to the twisting in the clearance of the workpiece.
Once the blind rivet stud 105b has been completely incorporated in the bore 201, and once the screw 155b has been spun on the internal thread 152, the lifting module generates a lifting movement which retracts the screw 155b into the mouthpiece 160b. As a result, forces are exerted on the blind rivet stud 105b that lead to the closing bead 116b being generated, and to the free axial portion 112 as a result of an interaction with the detent face 170b being outwardly enlarged in a manner so that the free axial portion 112 brings about a form-fit and/or friction-fit with the workpiece 200, in particular with the internal side of the clearance 201. At the end of this setting procedure, the blind rivet stud 105b is inserted in the workpiece 200 in a non-projecting manner at least on one side.
The features of the various aspects of the present invention described hereunder, or of the various exemplary embodiments, respectively, can be combined with one another unless this is explicitly precluded or is mandatorily precluded for technical reasons. The present invention is not limited to embodiments described herein; reference should be had to the appended claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2022 100 104.0 | Jan 2022 | DE | national |
