FASTENING SYSTEM ON A THREADED BOLT

Description

TECHNICAL FIELD

[0001] The invention falls within the field of fasteners, and relates more particularly to a threaded stud fastening system, particularly suitable for mounting a panel on an automobile body. PRIOR ART AND DISADVANTAGES OF PRIOR ART

[0002] As is known, panel fixing on automotive-type chassis is achieved by positioning the panel against the chassis, which includes protruding threaded studs that pass through holes made in the panel, and then screwing bolts into them to fix the panel against the chassis without any mechanical play remaining.

[0003] These screw-in fixings are often tedious for an operator, in addition to being very time-consuming.

[0004] One-piece clips are known to snap onto a threaded stud. This eliminates the need for a rotating bolt. However, these clips are designed for a specific type of threaded stud, and the operator must apply significant force to secure and lock the clip around the stud.

[0005] Also known from publication FR3091909 is a fixing piece for a threaded stud protruding from a base comprising a fixing piece equipped with several curved claws whose ends are intended to fit into the thread of a stud, and a cover piece intended to cover the fixing piece by exerting a force on the claws: this force deforms the claws which will consolidate the embedding of the ends of the claws in the thread and generate a tensile force against the base.

[0006] However, the tensile force generated by the fastener against the base after fixing depends greatly on the installation effort provided by the operator. OBJECTIVE OF THE INVENTION

[0007] The invention therefore aims to provide a fixing system for a threaded stud protruding from a base, the installation of which is carried out in an ergonomic and reproducible manner. DESCRIPTION OF THE INVENTION

[0008] To this end, the invention relates to a fastening system for a threaded stud protruding from a base, for example a motor vehicle chassis, according to claim 1.

[0009] The fastening system may also include the following optional features, considered individually or in all possible technical combinations: The mounting bracket includes means for locking the retaining tabs of the fastener in a constrained position. The fastening system is actuable between the position around the stud, in which the mounting bracket holds the four tabs of the fastener in their constrained position, and the tensioned fastening position on the stud. The mounting bracket includes means for connecting to the fastener when the retaining and tensioning tabs of the fastener are in the free position, the fastening system being in its tensioned fastening position on the stud. Each retaining tab of the fastener includes a window for interaction with the mounting bracket via its connecting means. The window is delimited by an upper portion for interaction with the mounting bracket via its locking means for the constrained position of the retaining tab in question.The window is delimited by an opposite lower portion from which the claw in question protrudes. The free end of each claw is concave. Each claw comprises a planar main body, and the free end of each claw is inclined relative to an extension plane of the claw body, the directions of inclination of the free ends of the two respective claws being opposite. Each tension tab of the fastening member comprises a base deformation main body and a free end portion for cooperation with the fastening member: a) by the locking means provided on the fastening member when the tension tab is in the constrained position, and b) by the connecting means provided on the fastening member when the tension tab is in its free position. The base is curved when the tension tabs are in their free position.The means for connecting and locking the mounting tabs are formed by two opposing protruding stops, each comprising: a) a retaining surface for the mounting tab considered in its free position, forming connecting means, and b) a locking shoulder provided on an inclined receiving surface for the upper portion of the mounting tab considered in its constrained position.The connecting and locking means for the tension tabs are formed by two opposing hollowed members, each comprising: a) a locking housing for the free end portion of the tension tab in its constrained position, and b) a grooved portion forming the connecting means and comprising a groove for housing the main body of the tension tab and two retaining edges for the free end portion of the tension tab, located on either side of the groove when the tension tab is in its free position. The locking housing in each hollowed member of the cocking piece is delimited by an inclined surface for receiving the free end portion of the tension tab.The fastening system includes a panel connection element intended to be fixed to the base, which element comprises a main body, panel fixing lugs, and a housing for the interconnected fastening and mounting parts. The fixing part includes connecting legs to the connection element, at least one end portion of each connecting leg being opposite an underside face of the main body.

[0010] The invention also relates to a method of installing a panel against a base with at least one fastening system as described above to a threaded stud protruding from said base, which method comprises the successive steps of: a) Positioning the panel against the base, the stud passing through the panel via an opening in said panel; b) Positioning the fastening system around the stud, with the tabs of the fastening piece in the constrained position and the base flat; c) Translating the fastening system into its constrained position along the threaded stud until the base is in contact with the panel; d) Translating the arming piece towards the panel relative to the fastening piece in contact with the panel, with the tabs in their constrained position;e) Simultaneous release of the tabs and actuation of the fixing piece towards its free fixing position around the stud, during which the free ends of the claws engage in the thread of the stud and during which the base moves from its flat position to its non-flat position by exerting a constraint against the panel directed perpendicularly to said base to eliminate any mechanical play between the fixing piece, the panel and the base. ; PRESENTATION OF THE FIGURES

[0011] Other features and advantages of the invention will become clear from the description given below, which is by way of example and not limitation, with reference to the attached figures: [ Fig. 1 ] There figure 1 represents a perspective view of the fastening system of the invention, which system is reinforced and pre-mounted on a panel; Fig. 2 ] There figure 2 represents a perspective view of the fastening system of the invention, which system is free; [ Fig. 3 ] There figure 3 represents a perspective view of a fastener component of the fastening system of the figure 1 which part is in a free, unconstrained position; [ Fig. 4 ] There figure 4 illustrates a side view of the mounting part of the figure 3 in a free position; Fig. 5 ] There figure 5 illustrates a side view of the mounting part of the figure 3 in a constrained position. DETAILED DESCRIPTION OF THE INVENTION

[0012] It is first clarified that in the figures, the same references designate the same elements regardless of the figure in which they appear and regardless of the form in which those elements are represented. Similarly, if elements are not specifically referenced in one of the figures, their references can easily be found by referring to another figure.

[0013] It is also specified that the figures essentially represent one embodiment of the object of the invention, but that there may be other embodiments which meet the definition of the invention.

[0014] The invention relates to a fastening system 1 by snapping to a threaded stud 34, and finds its application in the field of fastening industrial parts, and in particular in the field of fastening accessories to a chassis 42 or an automobile body.

[0015] With reference to figures 1 à 5 , the fastening system 1 of the invention comprises a fastening piece 2 to the threaded stud 34 and an arming piece 11 of said fastening piece 2.

[0016] The fixing piece 2, made of metallic material, typically steel, will now be described. This piece is particularly visible in its free, unconstrained position on the figures 2 And 4 , and in a constrained armed position on the figure 5 .

[0017] The fastening piece 2 extends along a longitudinal axis and comprises a generally rectangular base 3, which base 3 includes an inner face and an opposite outer face. The base 3 includes at its center a frustoconical central portion 45 projecting from the inner face of the base 3 and having at its center a cylindrical through-hole 4 through which the threaded stud 34 is intended to be housed. The through-hole 4 has a diameter greater than the diameter of the threaded stud 34.

[0018] The fixing piece 2 further includes two opposing retaining tabs 7, projecting from two opposing longitudinal edges 8 of the inner face of the base 3. These retaining tabs 7 are elastically deformable and can be actuated between a free retaining position and a constrained—or reinforced—position. The transition from the free position to the constrained position is achieved by separating the distal ends of said retaining tabs 7.

[0019] Each inset tongue 7 includes a window 15 delimited by a lower portion 17 integral with the considered edge 8 of the base 3, and an opposing upper portion 16. The upper portion 16 also extends in a plane secant with respect to an extension plane of the rest of the inset tongue 7.

[0020] The fastening piece 2 also includes two opposing claws 5, each comprising a main flat body 19 extending from the lower portion 17 of the considered recessed tab 7, and a distal free end 6 for cooperation with the thread 35 of the stud 34. The free ends 6 of the two respective claws 5 are opposite each other, on either side of the through hole 4. To ensure a larger surface area of ​​cooperation between the free end 6 of each claw 5 and the thread 35 of the stud 34, said free end 6 of each claw 5 has a concave shape. In other words, the concave shape of the free end 6 of each claw 5 ensures linear contact between said free end 6 and the threaded stud 34.

[0021] Furthermore, the free end 6 of each claw 5 has the same orientation as the thread 35 of the stud 34. For example, if the stud has a horizontal thread, the main body 19 and the free end 6 of each claw 5 extend in the same plane. If the stud 34 has a triangular thread 35, like the one shown in the figure 1 , then the free end 6 of the claw 5 is inclined relative to an extension plane of the claw 5, so as to allow insertion of the entire free end 6 of the claw 5 into the thread 35 of the stud 34. In the case of a fastener 2 adapted to a triangular thread 35, the directions of inclination of the free ends 6 of the two respective claws 5 are opposite.

[0022] The claws 5 are mechanically connected to the retaining tabs 7. Thus, when the retaining tabs 7 are in their free position, the claws 5 are configured to engage in the thread 35 of the stud 34. Conversely, when the retaining tabs 7 are in their constrained position, the claws 5 are in a position where their free ends 6 are disengaged from the thread 35 of the stud 34. Indeed, the transition from the free position to the constrained position of the retaining tabs 7 causes the distal free ends 6 of the opposing claws 5 to move apart.

[0023] The fixing piece 2 also includes two opposing tension tabs 9, projecting from two opposing transverse edges 10 of the inner face of the base 3. The tension tabs 9 are elastically deformable by bringing the distal free ends 21 of said tension tabs 9 closer together. They are thus actuable between a free position in which the base 3 of the fixing piece 2 is non-planar and a constrained - or armed - position in which the base 3 is planar ( figure 5 ).

[0024] More specifically, when the tension tabs 9 are in their free position, the opposite outer face of the base 3 of the fastener 2 has a concave curved profile. Alternatively, when the tension tabs 9 are in their free position, the outer face of the base 3 has a broken-line profile (see the figure 4 ), with a flat central zone and two inclined extreme zones, the angle between the central zone and the extreme zone considered being less than 180° at the level of the external face of the base 3 of the fixing piece 2.

[0025] In order to adjust and limit the force required to move the tension tabs 9 from their free position to their armed position, U-shaped through grooves 46 can be provided in the base 3 of the fixing piece 2.

[0026] Each tension tab 9 is T-shaped and comprises a main body 20 projecting from the base 3 of the fastener 2 and a free end portion 21 forming the distal end, which extends perpendicularly to said main body 20, i.e., parallel to the longitudinal axis. The free end portion 21 also extends in a plane intersecting a plane of extension of the remainder of the tension tab 9.

[0027] Finally, the fixing piece 2 includes four transverse connecting legs 32 projecting from the vertices of the base 3, perpendicular to the opposite longitudinal edges 8 of said base 3.

[0028] The armament part 11, preferably made of plastic or composite material and assembled to the fixing part, will now be described.

[0029] The armament piece 11 is at least partly housed in a space delimited by the four tabs 7, 9 of the fixing piece 2, and extends along a second longitudinal axis which coincides with the longitudinal axis of the fixing piece 2.

[0030] The weapon part 11 comprises a main body 36 with a rectangular cross-section in which a through hole 14 is provided for receiving the threaded stud 34. The hole 14 shown on the figures 1 et 2 presents in section a rectangular shape, but any shape of section is conceivable without departing from the scope of the invention provided that the orifice 14 allows the housing of the threaded stud 34. The two orifices 4, 14 respectively of the fixing piece 2 and of the arming piece 11 extend along the same axis perpendicular to the longitudinal axis and to a transverse axis of the fixing system, which axis will be referred to in the following as the vertical axis.

[0031] The main body 36 of the weapon part 11 comprises an upper face, an opposite lower face facing the base of the fixing part, and four lateral faces 37, 38 of which two longitudinal lateral faces 37 and two transverse lateral faces 38.

[0032] The arming piece 11 includes locking means in constrained position 23 of the fixed tabs 7, locking means in constrained position 22 of the tension tabs 9, and connecting means 12, 13 to the fixing piece 2 when the fixed tabs 7 and tension tabs 9 are in their free position.

[0033] With reference to the figure 2 , the structure of the weapon part 11 forming the linking means 12, 13 and locking means 22, 23 will be described.

[0034] The arming piece 11 comprises two opposing hollow members 25 respectively fixed to the two opposing transverse side walls 38 of the main body 36 of the arming piece 11. Each hollow member 25 comprises a grooved portion 13 - which forms the means of connection of the fixing piece 2 when the tension tabs 9 and the recess 7 are in the free position - having a longitudinal groove for housing 26 of the main body 20 of the tension tab in question 9 and two longitudinal retaining edges 27 of the free end portion 21 of the tension tab 9, which longitudinal retaining edges 27 extend on either side of the housing groove 26.

[0035] The longitudinal retaining edges 27 project from the considered transverse side wall 38 of the main body 36 of the cocking member 11. The width of the housing groove 26 is greater than or equal to the width of the main body 20 of the considered tensioning tab 9, and less than the width (i.e., a dimension perpendicular to the longitudinal axis) of the free end portion 21 of said tensioning tab 9. Furthermore, the longitudinal retaining edges 27 extend obliquely with respect to the considered transverse side face 38 of the main body 36 of the cocking member 11 and towards the lower face of said main body 36. Obliquely means a direction of extension of the retaining edges 27 that is neither parallel nor perpendicular to the considered transverse side face 38. Finally, each grooved portion 13 includes a transverse edge 39 forming the distal end of the hollowed-out member 25.

[0036] Thus, each housing groove 26 is delimited by the considered transverse side wall 38 of the main body 36 of the armament piece 11, by the two longitudinal retaining edges 27 and by the distal end transverse edge 39.

[0037] Each hollow element 25 further comprises a housing 22 for the free end portion 21 of the tension tongue 9 – which forms the locking means in the constrained position of the tension tongue 9 – extending between the transverse side wall 38 and the housing groove 26 of the grooved portion 13. This locking housing 22 for the free end portion 21 of the tension tongue 9 extends in a transverse direction and has a width greater than or equal to the transverse dimension of the free end portion 21 of the tension tongue 9. In addition, each locking housing 22 is delimited by two inclined receiving surfaces 28 for the free end portion 21 of the tension tongue 9, formed in the walls of the respective longitudinal retaining edges 27 on either side of the housing groove 26.Thus, the surface contact between the free end 21 of the tension tongue considered 9 and the inclined receiving surfaces 28 is maximized, which improves the locking in the constrained position of the tension tongue 9. Moreover, these inclined surfaces 28 each extend to two respective shoulders (not shown) provided in the walls of the respective longitudinal retaining edges 27 on either side of the housing groove 26. These shoulders allow the fastening piece (2) armed to be retained in the arming piece (11).

[0038] The arming piece 11 further includes two opposing stops 24 which project from the opposing longitudinal lateral faces 37 of the main body 36 of said arming piece 11. These stops 24 form locking beaks for the recessed tabs 7 in their constrained position.

[0039] Each stop 24 includes a superior connecting surface 12 which extends perpendicularly from the considered longitudinal lateral face 37 of the main body 36 of the arming piece 11. This superior surface forms the connecting means of the fixing piece 2 when the tension tabs 9 and the fixed tabs 7 are in the free position.

[0040] The stop 24 also includes an inclined locking surface 47 towards the lower face of the main body 36 of the arming piece 11 and extending from the upper face 12 of the stop 24, so that the stop has a triangular profile.

[0041] A locking shoulder 23 is formed in this inclined surface 47, which provides the locking means for the considered fixed tongue 7 in its constrained position. The lateral surface 43 of the shoulder 23 is parallel to the upper portion 16 of the considered fixed tongue 7 in the constrained position, so that the surface contact between the upper portion 16 of the considered fixed tongue 7 and the lateral surface 43 of the shoulder 23 is maximized, which improves the locking of the fixed tongue 7 in the constrained position.

[0042] The attachment to a threaded stud 34 of the fastening system 1 will now be described.

[0043] Before use, the fastening system 1 is armed, i.e., the locking tabs 7 and tension tabs 8 are in their armed position, in other words under tension, as shown on the figure 1 .

[0044] The two locking tabs 7 are held under tension by the stops 24 – or locking claws – of the mounting piece 11: the upper cooperating portion 16 of each locking tab 7 cooperates with the shoulder 23 of the stop 24 of the mounting piece 11. This has the effect of spreading the locking tabs 7 apart in a transverse direction, and concomitantly of spreading the distal free ends 6 of the two claws 5 apart so that they are disengaged from the thread 35 of the stud 34. In this way, the fixing piece 2, when the locking tabs 7 are engaged, can slide without resistance along the threaded stud 34.

[0045] The two tension tabs 9 are also held under tension by being housed in the locking housings 22 of the hollow parts 25. The arming piece 11 tends under these conditions to bring the free ends 21 of the tension tabs 9 closer together, which has the effect of deforming the base 3 of the fixing piece 2, and more specifically of flattening said base 3.

[0046] When an operator installs the fastening system 1 around the stud 34, he grasps the arming piece 11 and inserts the stud 34 into the two through holes 4, 14 respectively in the fastening piece 2 and the arming piece 11.

[0047] Advantageously, the cocking member 11 comprises two opposing flexible tabs (not shown) that project from the inner face of the opening 14 of the main body 36 of said cocking member 11, each extending to a free distal end, these distal ends being opposite each other. The distance between the two flexible tabs is less than the diameter of the stud 34, so that when the stud 34 is inserted into the openings 4, 14 of the cocking system 1 in the cocked position, the claws 5 of the fastening member 2 are disengaged from the thread 35 of the stud 34, but the flexible tabs of the cocking member 11 are in contact with the stud 34, thus ensuring that the fastening system 1 is held around the stud 34.The resistance force exerted by these flexible tabs is low, i.e. less than 20 newtons, which offers the double advantage of allowing pre-installation of the fastening system 1 around the stud 34 before final fixing, while allowing the operator to remove the fastening system 1 still armed from the stud 34.

[0048] To install the fastening system 1, the operator then moves the fastening system 1 around the stud 34 until the outer face of the base 3 of the fastening piece 2 comes into contact with the surface from which the stud 34 protrudes, for example the frame 42. Alternatively, when the operation aims to press a panel 41 against the base 42, the operator moves the fastening system 1 around the stud 34 until the outer face of the base 3 of the fastening piece 2 comes into contact with the panel 41.

[0049] By the force of pressure exerted by the operator on the upper face of the armament piece 11, the latter continues its translational movement towards the chassis 42 while the fixing piece 2 remains immobile, the base being in contact with the panel: there is therefore a relative translational movement of the armament piece 11 with respect to the fixing piece 2. The effort required to be exerted by the operator to ensure the translation of the armament piece 11 with respect to the fixing piece 2 is relatively low, between 30 and 50 newtons.

[0050] This relative movement causes, simultaneously, on the one hand, the displacement of the distal end parts 21 of the tension tabs 9 out of the locking housings 22, and on the other hand, the disengagement of the upper portions 16 of the recess tabs 7 out of the shoulders 23 provided in the locking stops 24 of the arming part 11.

[0051] The four tabs 7, 9 of the fastening piece 2 then move simultaneously from their armed position to their free position: the main body 20 of each tension tab 9 is found in the housing groove 26 of the arming piece 11, while the upper portion 16 of each recessed tab 7 comes into contact with the upper connecting surface 12 of the stop 24. This transition from the constrained position to the free position of the tabs 7, 9 is abrupt - a few hundredths of a second - and produces a characteristic sound perfectly recognizable by the operator installing the fastening system 1, which indicates to him that the fastening piece 2 has indeed been actuated to its free position and that it is in place around the threaded stud 34.

[0052] Furthermore, the upper part 21 of each tensioning tab 9 is retained in the housing groove 26 by the distal end 39 of the grooved portion 13, while the stops 24 of the bolt 11 are housed in the windows 15 of the recessed tabs 7. This ensures the connection between the fastener 2 and the bolt 11 while allowing free movement of the bolt 11 relative to the fastener 2. The fastening system 1 is then in a tensioned fastening position on the stud 34, as shown in the figure 2 .

[0053] Indeed, when the four tabs 7, 9 move from the armed position to the free position, the free ends 6 of the claws 5 of the fastener 2 engage in the thread 35 of the stud 34, while the base 3 of the fastener 2 returns to its non-planar free position, exerting a clamping force against the frame 42 and the panel 41. This force, which is greater than or equal to 50 newtons, eliminates any mechanical play between the panel 41, the frame 42, and the fastener 2. Furthermore, the force exerted by the fastener 2 against the frame 42 and the panel 41 depends on the material and shape of the fastener 2.Thus, if all the fasteners 2 of several fastener systems 1 are identical, then the forces exerted by these fasteners 2 against the panel 41 and the frame 42 from which the studs 34 protrude are all identical, which ensures a reproducible installation of the fastener systems 1 around the studs 34.

[0054] The fastening system 1 installed around the stud 34 is designed to resist pull-out, in particular a pull-out force directed in the opposite direction to the clamping force of the fastening piece 1 against the chassis 42. The pull-out resistance of the fastening piece 1 fixed to the threaded stud 34 is at least equal to 600 newtons.

[0055] Advantageously, the fastening system 1 absorbs the distancing stresses by deforming the fastening piece 2. This deformation of the fastening piece 2 tends to bring the distal ends 6 of the cooperation claws 5 closer together, causing an increase in the bearing force of said distal ends 6 of the claws 5 against the thread 35 of the stud 34. Thus, a force exerted on the fastening system 1 aimed at moving said fastening system 1 away from the chassis 42 will, on the contrary, tend to strengthen the fastening of the fastening system 1 around the threaded stud 34, provided that this distancing force remains less than the force required for pull-out.

[0056] In any case, the fixing system 1 installed around the stud 34 is easily removable, especially on a stud 34 with triangular thread 35, because the operator simply needs to unscrew the fixing system 1 in the conventional manner, like a conventional nut.

[0057] Finally, to allow the pre-assembly of the fastening system 1 on a panel 41, said fastening system 1 includes a connecting piece 30 to said panel 41 which will now be described, primarily with reference to the figure 1 .

[0058] This connecting piece 30 includes an annular wall 44 whose internal diameter allows the passage of the arming piece 11 and the mounting tabs 7 and tension tabs 9 of the fixing piece 2, but not of the connecting legs 32 which are opposite an underside of this annular wall 44.

[0059] The connecting piece 30 further includes a cylindrical wall 40 which projects from the lower face of the annular wall 44, and a plurality of deformable snap-on tabs 33 which extend from the free edge of the cylindrical wall 40.

[0060] This connecting piece 30 allows the fastening system 1 to be pre-assembled on the panel 41 by placing the assembled fastening pieces 2 and 11 against the panel 41, so that the holes 4, 14 of the fastening pieces 2 and 11 of the fastening system 1 are opposite a through hole 49 provided in the panel 41. The connecting piece 30 is then fixed to the panel 41 by snapping the snap-on tabs 33 into through recesses provided 48 for this purpose and made in the panel 41 ( figure 1 ).

[0061] According to an alternative embodiment not shown, the connecting piece 30 comprises two opposing tabs which extend from the free edge of the cylindrical wall 40 perpendicularly to the latter, which tabs allow a sliding mounting in a groove provided in the panel 41.

[0062] The assembly between the fixing parts 2 and the arming parts 11 are thus retained by the connecting part 30, and the distance separating two opposite connecting legs 32 of the fixing part 2 being less than the internal diameter of the orifice 31 of the connecting part 30, there is a clearance of this assembly to facilitate the positioning of the fixing system 1 in relation to the stud 34 during installation.

[0063] Advantageously, the invention provides a mounting panel 41 for a plurality of studs 34 protruding from a vehicle chassis 42, which panel 41 comprises a plurality of pre-assembled mounting systems 1. The simultaneous mounting of a plurality of mounting systems 1 is thus made possible. Attachment to the studs 34 is not only easier and more reproducible, but also faster.

Claims

1. A fastening system (1) with a threaded stud (34) projecting from a base, for example a motor vehicle chassis, comprising: a) a fastening part (2) comprising: i) a base (3) provided with a through-opening (4) intended to receive the threaded stud (34), ii) two opposing claws (5) each comprising a free end (6) for cooperating with the thread (35) of the stud (34), said free ends (6) of the two claws (5) are facing each other on either side of the opening (4), and iii) two interlocking tabs (7) projecting from two first opposing edges (8) of the base (3) and mechanically connected to the respective two cooperating claws (5), said interlocking tabs (7) are elastically deformable between a free position for interlocking the free ends (6) of the claws (5) into the thread (35) of the stud (34) and a constrained position for spacing said free ends (6) of the claws (5) away from the thread (35) of the stud (34). iv) two tension tabs (9) projecting from two second opposing edges (10) of the base distinct from the first edges (8), said tension tabs (9) are elastically deformable between a free position wherein the base (3) is non-planar and a constrained position wherein the base (3) is planar b) a cocking part (11) of the fastening part (2) comprising: i) an opening (14) intended to receive the threaded stud (34), and ii) means for locking in the constrained position (22) the tension tabs (9) of the fastening part (2); said fastening system (1) is actuatable between a position for fitting around the stud (34) wherein the cocking part (11) holds the tabs (9) of the fastening part (2) in their constrained position, and a position for fastening under tension to the stud (34).

2. The system according to the preceding claim, characterized in that: the cocking part (11) comprises means for locking in the constrained position (23) the interlocking tabs (7) of the fastening part (2), said fastening system (1) is actuatable between the position for fitting around the stud (34) wherein the cocking part (11) holds the four tabs (7, 9) of the fastening part (2) in their constrained position, and the position for fastening under tension to the stud (34).

3. The system according to the preceding claim, characterized in that the cocking part (11) comprises connecting means (12, 13) to the fastening part (2) when the interlocking tabs (7) and the tension tabs (9) of the fastening part (2) are in the free position, the fastening system (1) being in its position for fastening under tension to the stud (34).

4. The system (1) according to claim 2 or 3, characterized in that each interlocking tab (7) of the fastening part (2) comprises a window (15) for cooperating with the cocking part (11) by its connecting means (12).

5. The system (1) according to the preceding claim, characterized in that the window (15) is delimited by an upper portion (16) for cooperating with the cocking part (11) by its means for locking in the constrained position (23) of the interlocking tab under consideration (7).

6. The system (1) according to claim 4 or 5, characterized in that the window (15) is delimited by an opposite lower portion (17) from which the claw (5) under consideration projects.

7. The system (1) according to any one of claims 1 to 6, characterized in that the free end (6) of each claw (5) is concave.

8. The system (1) according to any one of the preceding claims, characterized in that each claw (5) comprises a planar main body (19) and in that the free end (6) of each claw (5) is inclined relative to a plane of extension of the body (19) of the claw (5), the directions of inclination of the free ends (6) of the two respective claws (5) being opposite.

9. The system (1) according to any one of the preceding claims, characterized in that each tension tab (9) of the fastening part (2) comprises a main body (20) for deforming the base (3) and a free-end portion (21) for cooperating with the fastening part (11): a) by the locking means (22) provided on the cocking part (11) when the tension tab (9) is in the constrained position and, b) by the connecting means (13) provided on the cocking part (11) when the tension tab (9) is in its free position.

10. The system (1) according to any one of the preceding claims, characterized in that the base (3) is curved when the tension tabs (9) are in their free position.

11. The system (1) according to any one of claims 3 to 10, characterized in that: a) The connecting means (12) and the locking means (23) of the interlocking tabs (7) are formed by two opposing projecting stops (24) each comprising: i) a retaining surface (12) of the interlocking tab (7) under consideration in its free position forming the connecting means (12), and ii) a locking shoulder (23) arranged on an inclined receiving surface of the upper portion (16) of the interlocking tab (7) under consideration in its constrained position b) The connecting means (13) and the locking means (22) of the tension tabs (9) are formed by two opposing hollowed members (25) each comprising; i) a locking housing (22) for the free-end portion of the tension tab (9) under consideration in its constrained position, and ii) a grooved portion forming the connecting means (13) and comprising a housing groove (26) for the main body (20) of the tension tab (9) and two retaining edges (27) of the free-end portion (21) of the tension tab (9) arranged on either side of the groove (26) when said tension tab (9) is in its free position.

12. The system (1) according to the preceding claim, characterized in that the locking housing (22) arranged in each hollowed member (25) of the cocking part (11) is delimited by an inclined receiving surface (28) for the free-end portion (21) of the tension tab (9).

13. The system (1) according to any one of the preceding claims, characterized in that it comprises a connecting element (29) to a panel (41) intended to be fastened to the base, said element (29) comprises a main body (30), fastening legs (33) to the panel (41) and a housing (31) for the fastening (2) and cocking (11) parts connected to each other.

14. The system (1) according to the preceding claim, characterized in that the fastening part (2) comprises connecting legs (32) to the connecting element (29), at least an end part of each connecting leg (32) being vis-a-vis a lower face of the main body (30).

15. A method for installing a panel against a base with at least one fastening system (1) according to any one of claims 2 to 14 to a threaded stud (34) projecting from said base, said method comprising the successive steps of: a) Placing the panel against the base, the stud (34) passing through the panel by an opening formed in said panel b) Placing the fastening system (1) around the stud (34), the tabs (7, 9) of the fastening part (2) being in the constrained position and the base (3) being planar; c) Translation of the fastening system (1) into its constrained position along the threaded stud (34) until the base (3) comes into contact with the panel d) Displacement in translation of the cocking part (11) in the direction of the panel relative to the fastening part (2) in contact support against the panel, the tabs (7, 9) being in their constrained position e) Concomitant release of the tabs (7, 9) and actuation of the fastening part (2) toward its free fastening position around the stud (34), during which the free ends (6) of the claws (5) engage in the thread (35) of the stud (34) and during which the base (3) passes from its planar position to its non-planar position while exerting a force against the panel directed perpendicularly to said base (3) to eliminate any mechanical play between the fastening part (2), the panel and the base.