Bolt fasteners

Abstract

The invention relates to a bolt fastener, which comprises a plurality of fixing devices, which are arranged radially around a receiving space for a bolt and are axially pivotable, wherein the fixing devices have engagement surfaces for engaging with the bolt in the direction of the axial receiving space for tightening the bolt, and bearing surfaces at diametrically opposite ends, by which the fixing devices are supported to prevent outward movement, wherein bearing devices for the bearing surfaces are also provided, which act together with the bearing surfaces in a supporting manner, wherein the bearing surfaces and the bearing devices are dimensioned so that they are disengaged when the fixing devices are pivoted in a direction opposite to the insertion direction of the bolt, wherein the radial spacing between the bearing devices and the bolt installed in the receiving space is less than the entire extension range of the fixing devices.

Description

[0001] The invention relates to a bolt fastener.

[0002] It is common practice, in particular in motor vehicles and also in aircraft, to provide fastening bolts on the vehicle body or other fuselage, which fastening bolts project from the fuselage or vehicle body and are used in this case for arranging components, assemblies, holders or the like.

[0003] This bolt is normally a bolt with an outer profile, and this outer profile can be realized by the bolt fastener. In the simplest case, this bolt especially can have a standardized thread, and corresponding counterpart (for example nut) can be screwed on the thread of this bolt.

[0004] Furthermore, it is common to push the securing element onto the thread.

[0005] In the case of plastics, such bolts can be mounted on the surface by gluing, friction welding or similar processes, while in the case of metal bodies or fuselages it is common to fasten such fuselages using the joining processes common to metal materials, but in particular by welding.

[0006] In particular, elements in motor vehicles are nowadays fastened using such screws, for example on trim elements.

[0007] EP 3 444 485 A1 discloses a fastening element and a fastening assembly, wherein the fastening assembly is intended to be placed on a fastening bolt, which has a fastening bolt head which is pushed through an opening into the device and whose undercut engages behind the device to achieve fastening. In order to maintain the fastening under stress, there is an elastic element.

[0008] Furthermore, it is known from the prior art to fasten trim elements, in particular door trim elements of a motor vehicle, in a body opening, in particular with anchor foot fasteners.

[0009] In known fastening mechanisms, the fastening must be performed blindly, ie the engagement of each individual fastening element is not visible.

[0010] The object of the present invention is to provide a bolt fastener which can be assembled and removed blindly.

[0011] Advantageous developments are characterized by the features described in the dependent claims.

[0012] The screw fastener according to the invention is designed in such a way that, on the one hand, fastening with the screw takes place reliably, but blind removal is also possible.

[0013] In this case, the holding forces in the screw-type fastener are structurally mitigated so that a minimum holding force is reliably achieved for holding the screw-type fastener and thus the component using one or more screws.

[0014] Furthermore, the invention makes it possible to loosen the screw fastening even without further manipulation using tools and to remove the screw fastening and the component suspended therefrom (eg a door trim) in a non-destructive manner and to fasten them again using the same screw fastening.

[0015] The inventor has found that certain minimum and maximum forces need to be observed for the non-destructive assembly and removal (also repeated removal and assembly) desired by the manufacturer. In particular, the requirements of repeated assembly and removal can already be met with the present invention when producing motor vehicles.

[0016] In the event of repairs, in particular when the panel element must be dismantled, the panel element can be removed and mounted again using the same device with the aid of the invention.

[0017] The present invention relates to a bolt fastener, which includes a plurality of fixing devices, which are arranged radially around a receiving space for a bolt and are axially pivotable; wherein the fixing devices have an engagement surface for engaging with the bolt in the direction of the axial receiving space for tightening the bolt, and have supporting surfaces at diametrically opposite ends, and the fixing devices are supported by these supporting surfaces to prevent outward movement, wherein supporting devices for these supporting surfaces are also provided, and these supporting devices act together with these supporting surfaces in a supporting manner, wherein the dimensions of the supporting surfaces and the supporting devices are determined so that they are disengaged when the fixing devices are pivoted in a direction opposite to the insertion direction of the bolt, wherein the dimensions of the radial spacing between the supporting device and the bolt installed in the receiving space are determined to be smaller than the entire extension range of the fixing devices.

[0018] Advantageously, the fixing devices are arranged in a suspended manner on axially and radially elastic spring arms, wherein the fixing devices are arranged on the spring arms with lateral regions between the contact surfaces and the end surfaces.

[0019] In the present invention, advantageously, the support surface of the fixing element is designed with a convex curvature, and the support device is designed as a notch with a corresponding concave curvature.

[0020] Furthermore, the concave curvature of the notch can be oriented such that the curvature does not extend beyond a horizontal plane relative to the axial insertion direction.

[0021] It is also advantageous if radially inwardly extending guide cheeks are arranged on both sides of the groove, which guide cheeks laterally limit the movability of the fixing devices.

[0022] In one embodiment, the fixing means are designed as blocking elements which are substantially cuboid elements which extend radially outwards from the receiving space and which have, on a face radially facing the receiving space, a curved engagement surface for engagement with a fastening bolt.

[0023] It is furthermore advantageous if the engagement surface is designed in particular to be radially curved and to be formed with a sawtooth-like and / or thread-segment-like contour as a corresponding engagement means for a thread or a contour of a fastening screw protruding through the insertion opening.

[0024] It is also advantageous if elastic arms are arranged on both sides of the blocking elements at a radially inner position, wherein the elastic arms initially extend inwardly in parallel from the inner surface of the outer wall and are bent towards the blocking elements, wherein the elastic arms terminate in free ends, wherein the elastic arms are arranged on the side faces of the blocking elements at the height of the free ends.

[0025] It is also advantageous that the elastic arms and the blocking elements are arranged relative to each other so that: in a powerless and unloaded state, the blocking elements extend obliquely toward the axial center or toward the receiving space in the insertion direction of the bolt, so that when the bolt is inserted, the blocking elements can pivot in the insertion direction to ensure that the bolt passes therethrough; and when the bolt is retracted, the bolt is pivoted into the receiving space so that the blocking elements are supported on the grooves with their bearing surfaces on the one hand and engage to the contour of the bolt with the engaging devices of the engaging surfaces on the other hand.

[0026] In an advantageous embodiment, an assembly unit is formed, which comprises a screw fastener and an anchoring clip, wherein the anchoring clip has a screw and there are locking devices on the anchoring clip, which interact with corresponding locking devices of the screw fastener in a locking manner, so that the locking is released and the screw fastener can be pushed completely onto the screw only when the anchoring clip is completely locked in the opening provided for this purpose.

[0027] The invention is explained by way of example with reference to the accompanying drawings. In the drawings:

[0028] Figure 1 : A bolt fastener according to the present invention is shown in a three-dimensional side view;

[0029] Figure 2 : A perspective view from the side showing the bottom of the bolt fastener according to the present invention;

[0030] Figure 3 : A top portion of a bolt fastener according to the present invention is shown in a three-dimensional side view;

[0031] Figure 4 : shows a bolt fastener on a flat member before the bolt fastener is tightened to the bolt;

[0032] Figure 5 :Shows the bolt fastener assembly state according to Figure 4 Bolt fasteners;

[0033] Figure 6 : shows the bolt fastener according to the present invention and the flat component in a pre-assembled state with a bolt bracket or a clamping bolt;

[0034] Figure 7 :Relative to Figure 6 The view rotated by 90° shows the bolt fastener and the clamping bolt according to the invention;

[0035] Figures 8 to 11 : showing different stages of inserting a bolt into and extracting a bolt from a bolt fastener;

[0036] Fig.12 : A bolt fastener according to the present invention is shown in a top view in an unassembled state;

[0037] Fig.13 : shows the elastic arm of the bolt fastener and the connecting element for the blocking element;

[0038] Fig.14 : shows a bolt element and an elastic arm arranged thereon;

[0039] Fig.15 : A bolt fastener according to the present invention is shown in a side view;

[0040] Fig.16 : A bolt fastener according to the present invention is shown in a top view of the bottom;

[0041] Fig.17 : A bolt fastener according to the present invention is shown in a top view;

[0042] Fig.18 : shows another embodiment in which the bolt fastener according to the present invention is combined with an anchor clip;

[0043] Fig.19 :The three-dimensional diagram from below shows Fig.18 Components;

[0044] Fig. 20 :The three-dimensional diagram from above shows the Fig.19 components.

[0045] The bolt fastener 1 ( Figures 1 to 3) having a bolt fastener bottom 2 that can be fastened together ( Figure 2 ) and bolt fastener top 3.

[0046] The structure consisting of the bolt fastener bottom 2 and the bolt fastener top 3 is essentially production-related and is intended to be exemplary here. Naturally, a one-piece production can also be easily achieved using suitable manufacturing methods, such as 3D printing.

[0047] The screw-type fastener base 2 has a base wall 4 , in the center of which a particularly circular insertion opening 5 for a screw is arranged.

[0048] A plurality of bearing blocks 6 are provided around the insertion opening 5 and spaced apart from the insertion opening, in which bearing blocks bearing notches 7 are arranged. The bearing notches 7 are designed in this case so that on the surface of the bearing block 6 radially facing the insertion opening 5 there is first an inclined slope 8, which transitions to a substantially concavely curved notch 9, which has an arc length of, for example, one eighth to one quarter of a circle and transitions to another inclined top surface 10.

[0049] On both sides of each support block 6 or on both sides of each support notch 7 in a radial direction relative to the insertion opening 5

[0050] Guide cheeks 11 are formed in a projecting manner, which project radially beyond the notch 9 in the direction of the insertion opening 5 and delimit the space or interval therebetween with guide surfaces 12 .

[0051] In the case of a multi-part design of the screw-type fastener 1 consisting of the screw-type fastener base 2 and the screw-type fastener top 3 , locking tabs 14 pointing in the axial direction are present on the circumferential outer wall 13 .

[0052] The number of bearing notches 7 and bearing blocks 6 and correspondingly the double number of guide cheeks 11 is in principle freely selectable and is three in the example of the invention, so that three bearing blocks 6 and correspondingly six guide cheeks 11 are arranged symmetrically and radially distributed around the insertion opening 5 .

[0053] In accordance with Figure 2 In the embodiment of the invention, the surrounding wall 13 is circular, but its outer shape is not critical in the case of the screw fastener and can be adjusted, in particular, depending on the application and the component to be fastened.

[0054] The blocking element 15 is arranged at the level of the support block 6 on the top 3 of the fastener ( Figure 3 )middle.

[0055] The blocking elements 15 are substantially cuboid elements which extend radially outwards from an axial centre or an axial plane of the through-opening or insertion opening 5 .

[0056] An axial center or an imaginary cylindrical area in the screw fastener above the insertion opening 5 defines a receiving space 33 for the screw 30. The blocking element 15 has an engagement surface 16 facing the axial center or the receiving space 33.

[0057] The engagement surface 16 is designed to be radially curved and has a sawtooth-like or thread-segment-like profile as a counterengagement means for a thread or a profile of a fastening screw 30 protruding through the insertion opening 5 .

[0058] For this purpose, the blocking elements 15 are arranged radially in such a way that they protrude to a certain extent into the axial plane of the insertion opening 5 or into the receiving space 33 , so that they can achieve correct engagement with a bolt (not shown).

[0059] On the end face 17 opposite the engagement face 16 , the blocking element is designed with an axial curvature, wherein the radius of the axial curvature 18 preferably corresponds to the radius of the notch.

[0060] In order to hold the blocking element 15 radially in its position, spring arms 20 are arranged radially inside on each side of the blocking element 15 on a circumferential outer wall 19 , which preferably has a contour corresponding to or identical to that of the outer wall 13 .

[0061] The spring arm 20 initially extends inwardly parallel from the inner surface of the outer wall 19 and then bends toward the blocking element 15. For example, the spring arm is bent by 90°, but the size of the bend is not important. The spring arm 20 ends with a free end 21, wherein the spring arm 20 has supporting extensions 22 facing each other at the level of the free end 21, which are designed, for example, as thin cylinders and are connected to the spring arm 20 on its opposite sides and to the blocking element 15 on the side 23 of the blocking element 15.

[0062] During production, the axial angle of the blocking element 15 is preferably set such that the blocking element 15 extends obliquely upward toward the axial center.

[0063] Furthermore, the bolt-on top 3 has locking projections 24 on the outside of the outer wall 19 , which interact in a known manner with the locking tabs 14 in order to lock and hold the bolt-on top on the bolt-on bottom.

[0064] There may be a guide groove 25 radially inside the locking tab 14 and a corresponding guide protrusion 26 of corresponding shape on the bolt fastener top 3 below the locking protrusion 24 to ensure correctly positioned assembly.

[0065] In the state where the bolt fastener bottom and the bolt fastener top are assembled together or in the one-piece embodiment of the bolt fastener, the blocking element 15 is in the initial position ( Figure 8 ) with its curved portion 18 of the end face 17 being located in the region of the notch 9 and being arranged on elastic arms 20 or suspended on these elastic arms in a manner extending upwardly inclined relative to the axial center.

[0066] The support extension 22 here engages approximately to the radial center of the blocking element 15 between the end face 17 and the engagement face 16. If the fastening bolt 30 is pushed into the bolt fastener 1 through the insertion opening 5 ( Figure 8 ), the blocking element 15 can yield relative to the fastening bolt 30 in the direction of arrow 27 and further pivot in the insertion direction. After the bolt is fully inserted ( Fig. 9 ), the blocking element is slightly pivoted in the direction of the arrow 28 toward the longitudinal center and engages with its profiled engagement surface 16 to the correspondingly profiled surface 31 of the bolt 30. In this position, the bolt 30 is held in the bolt fastener with minimal force by the blocking element, wherein in this position the blocking element is still slightly tilted upwards in the direction of the transverse center, so that the blocking element is supported against the bolt at the rear side by the notch 9.

[0067] It is naturally self-evident that the number of blocking elements 15 corresponds to the number of slots 9 and in the example shown is, for example, three, but there may also be fewer or more blocking elements, wherein preferably the total number of engagement surfaces 16 or the arc length of the engagement surfaces 16 as a whole is slightly smaller than the full circle around the bolt and optionally there are gaps between the engagement surfaces 16 of the blocking elements 15.

[0068] To remove bolts and bolt fasteners ( Fig.10 , Fig.11 ), exerting a tensile force on the bolt fastener 1, thereby pulling the bolt out of the insertion opening 5.

[0069] This is initially prevented with a predetermined force, wherein the blocking element 15 is rotated further in the recess 9 according to the arrow direction 29 .

[0070] Due to this rotation and the pressure exerted by the bolt on the blocking element 15, the curved surfaces 17 come out of the notch 9 into the region of the inclined top surface 10, on which they slide radially outward. As a result, the blocking element 15 releases a withdrawal path for the tightening bolt, since the contact surface 16 is no longer in frictional engagement with the outer contour 31 of the bolt.

[0071] The notches 9 thus serve as counter-supports for the blocking elements 15, which act as pivotable fixings and can be pushed out of their support positions in the notches 9 against the force of the spring arms 20. The shape and dimensions of the notches 9 are thus designed so that when the blocking element 15 is pivoted in the retraction direction (i.e. in the horizontal position), it is pushed radially outwards from the support position or notches 9 due to the pressure of the bolts 30 and thus releases the bolts 30. The radial length between the notches 9 or their surface and the outer surface of the bolts is smaller here than the corresponding length of the blocking element 15, so that a corresponding pressure can be built up during the pivoting. This can optionally also be supported in that the connection area or the support projection 22 of the spring arms 20 is located axially above the notches 9, so that in the initial position of the blocking element 15, the spring arms 20 do not exert any force; however, when pivoting in the retraction direction, the spring arms 20 generate an axial force opposite to the retraction direction, which helps to lift out of the notches 9.

[0072] As soon as the bolt 5 is withdrawn from the bolt fastener, the blocking element 15 springs back again into its basic position extending slightly obliquely upwards by means of the spring arms 20 and the bolt fastener can be used again for locking operation.

[0073] In another advantageous embodiment, the bolt fastener according to the invention is combined with the anchor clip to form an assembly unit ( Figures 18 to 20 ).

[0074] In the assembly unit consisting of the bolt fastener 1 and the anchor clip bolt 40 according to the present invention, the bolt fastener 1 is designed in a substantially identical manner, but there are fixing devices between the bolt fastener 1 and the anchor clip bolt 40, which on the one hand ensure the correct position of the bolt fastener 1 on the anchor clip 40 and on the other hand ensure that the anchor clip 40 is correctly in place after assembly.

[0075] The anchoring clip 40 has an axial bolt 30 , wherein at one threaded end of the bolt 30 a support plate 41 is formed on the anchoring clip 40 in a manner known per se.

[0076] This plate 41 is slightly bent at or towards its circumferential edge 42 in the opposite direction to the direction of the screw 30 .

[0077] On the axial side diametrically opposite the bolt 30, the anchoring clip 40 is designed with an anchoring element 42, wherein the anchoring element 42 has an axially straight bracket 43, which allows the bolt to continue on the other side of the plate 41, and a locking arm or rear engagement arm 45 projects from the bracket at the end 44 opposite to the bolt 30 in a manner known per se.

[0078] The rear engaging arm 45 cooperates with the bent plate 42 in a known manner so that when the rear engaging arm engages behind an opening (particularly in a body panel), the rear engaging arm springs back outward and engages behind the hole, thereby particularly securing the rear engaging portion, while the plate 42 is also supported on the other side of the corresponding panel to prevent rattling.

[0079] In order to ensure that the anchor clip 40 fits correctly in the assembly opening (not shown), and to ensure that the bolt fastener can be fully pushed onto the anchor clip 40 only when the anchor clip fits correctly, a blocking finger 46 is designed on the assembly unit consisting of the bolt fastener 1 and the anchor clip 40 according to the present invention.

[0080] The blocking finger 46 is an angled element having a first leg 47 and a second leg 48. The first leg 47 rests on the plate 41 and extends outwardly from an area adjacent to the bolt 30 but not adjacent to it. The leg 47 ends with a bent end 49 which bends in the direction toward the outer edge 42 of the plate 41 but projects beyond the surrounding edge 42 in the direction toward the bracket 43 of the anchoring clip 40.

[0081] The blocking finger 46 is supported on the plate 41 so as to be pivotable towards the bolt 30 and away from it, wherein in its initial position the blocking finger is arranged such that the leg 48 is offset relative to the bolt 30 .

[0082] The leg 48 has at its free end 50 an outward locking step 51 which is designed, for example, as a right-angled recess.

[0083] The locking step 51 acts together with a locking step 52 which is designed as an inward edge of the region close to the bottom wall 4 of the screw fastener 1. The inward edge 53 forming the locking step 52 is slightly set back relative to the surrounding edge of the through-opening 5, thereby forming a receiving opening 54 for the leg 46.

[0084] Here, there may be at least one blocking finger 46, but there may also be a plurality of blocking fingers 46, for example three blocking fingers 46 ( Fig.19 ).

[0085] These parts work together as follows:

[0086] In the assembled state, the bolt fastener 1 is pushed onto the bolt so that the opening 54 is aligned with the blocking finger 46. The insertion is then stopped by the interaction of the locking steps 51, 52, since the corresponding locking edge 51 of the bottom wall 4 rests in the locking step 51 of the blocking finger 46. If the assembly unit consisting of the bolt fastener 1 and the anchoring clip 40 is now inserted into an opening in a panel, such as a body panel, this locking action remains effective until the anchoring clip 40 has been inserted to such an extent that the rear engagement arms 45 are released again after being pushed through the opening and spring back outwards. Due to the length of the rear engagement arms 45 towards their free ends, rear engagement only occurs when pressure is applied to the panel 41.

[0087] Due to this pressure, a force is also exerted on the free end 49 of the leg 47, which is thus pivoted upwards and the leg 46 is thereby pivoted towards the bolt 30, in particular until the locking steps 51, 52 are disengaged and the blocking finger leg 48 can fully enter the opening 54. If this happens, the bolt fastener can be released from its position in the Fig.18 The pre-assembled position shown in FIG. 3 is completely pushed onto the bolt 30. In this embodiment, it is advantageous that the bolt fastener can be used in a more variable manner, because in the state pre-assembled with the bolt, the bolt fastener can also arrange the bolt in an existing opening.

[0088] Naturally, this temporary locking and fixing effect can be achieved with any bolt fastener, as long as this bolt fastener is formed with a suitable corresponding bolt. The assembly unit is therefore not limited to the bolt fastener described above in any way. This represents an example of any possible bolt fastener.

[0089] It is advantageous in the present invention that the groove acts as a counter-support device together with a fixing device in the form of a blocking element, so that the fastening bolt is held in a fully inserted state and is prevented from being withdrawn, and after the maximum force has been applied or the maximum holding force has been exceeded, the fixing device is disengaged from its counter-support device by withdrawing the bolt, thereby releasing the friction fit between the fixing device and the guide bolt to be fixed.

[0090] It is also advantageous that in this construction, which can also be produced in a cost-effective manner, a reliable setting of minimum and maximum forces is permitted and that, furthermore, due to the articulated arrangement of the fixing device on the elastic arm (as guide and return device), the bolt fastener according to the invention can be used again for assembly after removal, so that, for example, interior trim panels of a motor vehicle can be dismantled and reinstalled.

[0091] List of Reference Numerals

[0092] 1 Bolt fastener 26 Guide protrusion

[0093] 2 Bolt fastener bottom 27 Arrow direction

[0094] 3 Bolt fastener top 28 Arrow direction

[0095] 4 Bottom wall 29 Arrow direction

[0096] 5 Insert the 30 bolt into the opening

[0097] 6 Support block 31 Contoured surface

[0098] 7 Support notch 33 Receiving space

[0099] 8 Inclined Slope 40 Anchor Clip Bolts

[0100] 9 Notch 41 Support plate

[0101] 10 inclined top surface 42 surrounding edge

[0102] 11 Guide cheek 43 Bracket

[0103] 12 guide surface 44 end

[0104] 13 surrounding outer wall 45 rear engagement arm

[0105] 14 Locking tab 46 Blocking finger

[0106] 15 blocking element 47 leg

[0107] 16 joint surface 48 leg

[0108] 17 Support surface 49 End

[0109] 18 Axial camber 50 Free end

[0110] 19 outer wall 51 locking member

[0111] 20 elastic arm 52 locking member

[0112] 21 Free end 53 Edge

[0113] 22 Support extension 54 Opening

[0114] 23 Side

[0115] 24 Locking protrusion

[0116] 25 Guide groove

Claims

1. A bolt fastener comprising a plurality of fixing devices (15) which are arranged radially around a receiving space for a bolt (30) and are axially pivotable, The fixing device (15) has an engagement surface (16) for engaging with the bolt (30) in the direction of the axial receiving space (33) for tightening the bolt (30), and the fixing device (15) has a bearing surface (17) at the diametrically opposite end, by which the fixing device (15) is supported to prevent outward movement, A support device (9) is also provided for the support surface (17), the support device cooperating with the support surface (17) in a supporting manner, wherein the bearing surface (17) and the bearing means (9) are dimensioned so that they are disengaged when the fixing means (15) is pivoted in a direction opposite to the insertion direction of the bolt (30), wherein the radial spacing between the support device (9) and the bolt (30) installed in the receiving space (33) is smaller than the longitudinal extension of the fixing device (15), wherein the fixing device (15) is designed as a blocking element, The fixing device (15) is arranged in a suspended manner on an elastic arm (20) which is elastic in the axial direction and the radial direction, and The support surface (17) of the fixing device (15) is formed with an axial curvature (18), and the support device (9) is designed as a groove with a corresponding, concave curvature.

2. The bolt fastener according to claim 1, The fixing device (15) is arranged on the spring arm (20) by means of a lateral area between the contact surface (16) and the support surface (17).

3. The bolt fastener according to claim 1, in, The concave curvature of the notch is oriented such that the curvature arc does not extend beyond a horizontal plane relative to the axial insertion direction.

4. The bolt fastener according to claim 1, in, Guide cheeks (11) extending radially inwards are arranged on both sides of the notch and laterally limit the movability of the fixing device (15).

5. The bolt fastener according to claim 1, in, The blocking element is a substantially cuboid element which extends radially outward from the receiving space (33) and has a curved engagement surface (16) on a surface radially facing the receiving space (33) for engagement with a fastening bolt (30).

6. The bolt fastener according to claim 1, in, The engagement surface (16) is designed to be radially curved and is formed with a profile of serrations and / or threaded sections as a corresponding engagement means for a thread or a profile of a fastening screw (30) protruding through the insertion opening (5).

7. The bolt fastener according to claim 5, in, On both sides of the blocking element, elastic arms (20) are respectively arranged at radially inner positions. The elastic arm (20) first extends inwardly from the inner surface of the outer wall (19) in parallel and bends toward the blocking element. wherein the elastic arm (20) terminates with a free end (21), The elastic arms (20) are arranged on the respective side faces (23) of the blocking element at the level of the free ends (21).

8. The bolt fastener according to claim 5, in, The elastic arm (20) and the blocking element are arranged relative to each other so that: in a powerless and unloaded state, the blocking element extends obliquely toward the axial center or toward the receiving space (33) in the insertion direction of the bolt (30), so that when the bolt is inserted, the blocking element can pivot in the insertion direction to ensure that the bolt (30) passes therethrough; and when the bolt is withdrawn, the blocking element is pivoted into the receiving space (33) by the bolt so that the blocking element is supported on the groove with its bearing surface (17) on the one hand and is engaged to the contour of the bolt with the engagement device of the engagement surface on the other hand.

9. An assembly unit comprising the bolt fastener according to claim 1, and an anchor clip (40), The anchoring clip has a bolt (30) and a blocking finger (46) is present on the anchoring clip (40), the blocking device cooperating with the corresponding locking steps (51, 52) of the bolt fastener (1) in a locking blocking manner, so that the blocking is released and the bolt fastener (1) can be completely pushed onto the bolt (30) only when the anchoring clip is completely locked in an opening provided for this purpose.

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