EXPANDER WITH IMPROVED CONSTRUCTION AND ROLLING ARRANGEMENT WITH SUCH AN EXPANDER

Description

[0001] The invention relates to an extender for a rolling assembly consisting of a tire and a rigid rim connected by an extender capable of providing a certain degree of elastic flexibility when subjected to an impact during rolling, as well as a rolling assembly incorporating it. A tire, as is known, comprises two beads intended to be mounted on the seats of a rim. The present invention relates to rolling assemblies in which a tire bead is not mounted directly on a rigid rim, but is mounted on a flexible extender, which is itself mounted on a rigid rim, and it relates more particularly to the design of such an extender.

[0002] A tire, a rim, and an extender, as discussed in the present invention, are usually described by a representation in a meridian plane, that is, a plane containing the axis of rotation of the tire. All these products (the tire, the rim, and the extender) are objects having a geometry of revolution with respect to the axis of rotation of the tire. The radial and axial directions respectively designate the directions perpendicular to the axis of rotation of the tire and parallel to the axis of rotation of the tire. In what follows, the expressions "radially" and "axially" mean respectively "along a radial direction" and "along the axial direction." The expressions "radially inside" and "radially outside" mean "closer to, and respectively farther from, the axis of rotation of the tire, along a radial direction."A median plane is a plane perpendicular to the tire's axis of rotation, positioned axially so as to intersect the tread surface approximately midway between the tire's bead. The terms "axially inside" and "axially outside" mean "closer to, or farther from, the tire's median plane, respectively, along the axial direction." Furthermore, a "radial cut" or "radial section" refers to a cut or section along a plane that contains the tire's axis of rotation. A "meridional cut" is a cut made along a meridian plane, and a meridian plane is defined as a plane parallel to and containing the tire's axis of rotation and perpendicular to the circumferential direction.By "circumferentially" we understand along a circumferential direction, we mean the direction which is substantially perpendicular to both the axial direction and to a radius of the tire (in other words, tangent to a circle whose center is on the axis of rotation of the tire).

[0003] Document WO2019 / 002792 describes an example of a flexible expander arranged between a tire bead and a rim. The rolling assembly according to this document comprises a tire, a rim, and two identical expanders. Considering the terminology mentioned above, and referring to the way an expander is mounted on a rim, such an expander comprises, axially from the inside out, an axially inner end called the expander bead, designed to secure the expander to the rim. Such an expander also comprises an axially outer end designed to receive and axially immobilize a tire bead. A body with a reinforcing frame connects the two axially inner and axially outer ends, respectively.

[0004] The extenders are mounted on a rim, which is a metal component, most often made of aluminum. The rim has a rim hook on each side, designed to secure the extender in the axial direction. A flexible extender must, on the one hand, exhibit a certain degree of elastic flexibility, for example, when impacting a curb or driving over a pothole, and on the other hand, it must have sufficient rigidity while rolling to ensure proper vehicle handling. To achieve this, such extenders are made from elastomeric materials, similar to those used in tire manufacturing, from which they borrow their appearance.

[0005] Thus, a wheel assembly, consisting of a rim and a tire mounted on the rim using two expanders, appears smaller in diameter than a conventional wheel used with a tire of the same size. However, the current design trend is to have the largest possible wheel, at least visually.

[0006] A solution was proposed in document WO2018 / 007751 on behalf of the applicant, which consists of attaching a decorative ring to the periphery of the extender. This decorative ring is chosen for its elastic deformation; it is a single piece and is fixed by means of a removable mechanical fastener on the circumference of the visible part of the extender. However, it has been observed that when the extender undergoes significant deformation, for example, when impacting a curb, the decorative ring can detach locally from the extender, leading to its loss while driving if it is not quickly reattached. This local detachment can also result from malicious acts while parked.Moreover, depending on the materials chosen for the production of the trim ring, the difference in coefficient of expansion of these materials compared to rubber can lead to the mechanical strength of the ring being vulnerable to changes in temperature.

[0007] The aim of the invention is to remedy the aforementioned disadvantages and to propose a design solution for an extender allowing robust attachment, even in the event of large deformations of the extender or when the wheel rotates at high speed, while allowing customization of the extender design by the user.

[0008] The invention therefore relates to an extender for a rolling assembly with axis of rotation XX' comprising a tire, having two beads and a rim, the extender being intended to ensure the connection between one of the beads and the rim, said extender comprising an axially inner end, an axially outer end and a body oriented mainly axially and disposed between said axially outer end and said axially inner end, so that, when mounted within the assembly, said axially inner end is intended to be immobilized on said rim by means of an internal reinforcing element, said axially outer end comprising an external reinforcing element is intended to receive a tire bead, characterized in that said axially outer end has a front face provided with several cavities distributed on its circumference,said cavities being open at the level of said face and made in such a way as to cooperate with removable fixing means for several adjacent inserts.

[0009] Two cavities distributed around the circumference of the front face are understood to be two cavities positioned side-by-side, leaving a gap between them. This gap allows for the creation of elastomeric bridges between the cavities on the circumference of the front face of the axially outer end of the extender. The geometric centers of the cavities may be located on the same diameter of the front face or on different diameters, for example, by staggering them. The front face is preferably a visible face of the extender. Preferably, the visible face is understood to be that of the axially outer face of the outer extender. The inner extender may be identical to or different from the outer extender; for example, if it is different, it may not have any added inserts.

[0010] The cavities according to the invention have fastening interfaces that can accommodate several independent rigid inserts. Since the inserts are relatively rigid, for example, metallic, the area separating two inserts fixed in their respective cavities is flexible. Furthermore, the cavities and their corresponding inserts are chosen to be quite small, their size being comparable to that of a local deformation experienced by the extender in the event of an impact against a curb, for example. This allows the extender to absorb deformation in the event of an impact to the wheel, without affecting the extender's external appearance and thus preserving its original design. The same applies when several rigid inserts, independent or connected by flexible links, are housed in several cavities distributed across the front face of the extender.Thus, in the event of an impact on the wheel, such an arrangement of independent inserts in a flexible support allows the support of the inserts to deform, while still retaining the inserts attached to it.

[0011] Preferably, the distance between two cavities or two inserts is comparable to the width of the front face of the axially outer end of the extender and, preferably, less than this width, and even more preferably less than the width of the insert. Thus, several inserts side-by-side give the visual impression of a continuous metallic, colored, etc., band.

[0012] The removable means for attaching the insert to the axially external end of the extender may include means for attaching the inserts by reversible elastic interlocking in the cavity or cavities of the axially external end of the extender. This allows for easy modification of the design of the visible part of the extender, while ensuring durable attachment of the inserts.

[0013] In one embodiment, the cavity can be designed to cooperate with spherical fastening means. This allows for easy fixation by simple axial pressure.

[0014] The depth of a cavity can be greater than its radius and less than its diameter, which ensures that the insert stays securely in the cavity.

[0015] In another embodiment, the cavity can be designed to cooperate with hook-type fastening means. This allows for simple and robust attachment of the insert within the cavity of the extender.

[0016] In one embodiment, the extender may include at least one circumferential row of cavities uniformly distributed around the circumference of said front face. Such a row of cavities, when they accommodate inserts, gives the visual impression of a continuous circle, and several rows reinforce this visual effect.

[0017] The expander can comprise two coaxial circumferential rows of cavities, with the cavities in one row being angularly offset from those in the other row. This results in a staggered arrangement of the cavities in the two coaxial rows, providing an even more pronounced circular visual effect.

[0018] In another embodiment, these cavities are formed as a plurality of grooves, uniformly distributed around the circumference of the front face. The grooves allow for the attachment of a generally elongated insert, which, when this insert is metallic, gives the extender an overall metallic appearance and thus creates the impression of a larger diameter wheel.

[0019] The cross-section of these grooves can have a shape similar to a dovetail. The grooves thus provide a robust mechanical attachment interface for inserts with a geometry that cooperates with that of the grooves that support them.

[0020] These grooves may have an open radially inner end and a closed radially outer end. This allows the inserts fixed in the grooves to be retained when subjected to the action of centrifugal force during rolling.

[0021] These grooves may be radial or they may each make a constant acute angle with the radial direction of the extender.

[0022] The said cavity or cavities may be made so that their radially outer end is located radially and / or axially recessed relative to the radially outer end of the said front face.

[0023] This allows for an assembly in which the protruding part of the insert is set back radially and / or axially from the radially outer end of said front face of the extender and protects the inserts when mounting the tire on the extender when forces are applied by the lower part of the tire on the radially upper end of the extender.

[0024] The invention also relates to an insert comprising removable fastening means and intended to cooperate with at least one of the cavities of the extender of the invention. Such an insert makes it possible to give the extender a desired design appearance, while protecting it from scraping against the curb.

[0025] The insert may include a plate with means for fixing it in at least two adjacent cavities. This simplifies the process of fixing the inserts.

[0026] The object of the invention is also achieved with an assembly comprising an extender according to and several inserts according to the invention.

[0027] The object of the invention is also achieved with a rolling assembly with axis of rotation XX' comprising a tire, having two beads, a rim and an extender according to the invention intended to ensure the junction between one of the beads and the rim, said extender being provided with inserts according to the invention.

[0028] The invention is described below with reference to the figures 1 to 23 Data provided for illustrative purposes only: there figure 1 is a meridional cross-sectional view of a rolling assembly comprising an extender according to the invention; the figure 2 is a partial front view of an assembly comprising an extender and inserts according to a first embodiment of the invention; the figures 3 to 6 are partial meridional cross-sectional views of an assembly comprising an extender with inserts according to different variants of the first embodiment of the invention; the figure 7 is a partial perspective view of an assembly comprising an extender and inserts according to a second embodiment of the invention and the figure 8 a partial meridional cross-sectional view of this assembly; the figure 9 is a partial front view of an assembly comprising an extender and inserts according to a third embodiment of the invention and the Figure 10 a partial cross-sectional view of this assembly; the figure 11 is a partial meridional cross-sectional view of an alternative embodiment of an extender according to the third embodiment of the invention; the Figures 12 and 13 are partial perspective views of the extenders and inserts according to variants of the third embodiment of the invention; the figure 14 is a partial perspective view of an extender according to a fourth embodiment of the invention and the figure 15 an enlarged view of the front face of the extensor of the figure 14 ; THE Figures 16 and 17 are a partial perspective view and respectively a partial perspective view at enlarged scale of an assembly comprising an extender and inserts according to a first variant of the fourth embodiment; the Figures 18 and 19are a partial perspective view and respectively a partial perspective view at enlarged scale of an assembly comprising an extender and inserts according to a second variant of the fourth embodiment; the Figure 20 is a front view of an assembly comprising an extender and inserts according to a fifth embodiment of the invention and the Figures 21 and 22 enlarged partial cross-sectional views of this assembly; the figure 23 is a front view of an extender according to a sixth embodiment of the invention.

[0029] In the various figures, identical or similar elements bear the same reference. Their description is therefore not systematically repeated.

[0030] Any range of values ​​designated by the expression "between a and b" represents the range of values ​​from more than a to less than b (i.e., bounds a and b excluded) while any range of values ​​designated by the expression "from a to b" means the range of values ​​from a to b (i.e., including the strict bounds a and b).

[0031] There figure 1The figure shows, in cross-sectional view, a rolling assembly according to the invention. This assembly has an axis of rotation X-X', and comprises two extenders 1, a tire 2, and a rim 3. The tire 2 has two bead 21. The rim 3 has two rim seats 31, each extended by a rim flange 32. The rim flange 32 has a radially external bearing surface 29 intended to support the body of the extender. The bearing surface 29 of the rim flange 32 is in contact with the extender 1 when the tire is mounted on the extenders and the extenders are mounted on the rim, with the tire inflated to the nominal pressure.

[0032] The extender 1 has an axially inner end 10 for mounting on one of the rim seats 31. It has an axially outer end 11 provided with an external reinforcing element 15, which is annular in shape, for example, made from a cable winding, and a body 12 oriented substantially axially and disposed between said axially outer end 11 and said axially inner end 10. The axially inner end 10 of the extender has an axially positioned face substantially perpendicular to the axis of rotation X-X', and is immobilized by being axially pressed against the rim flange 32, under the effect of the inflation pressure of the tire 2 and by means of a groove in the rim containing it. The axially outer end 11 has a shoulder 16 forming a face substantially perpendicular to the axis of rotation X-X'.The extender 1 comprises a seat 14 which receives the bead 21 of the tire. The bead 21 is immobilized by being axially pressed against the seat 14 against the shoulder 16 of the axially external end 11 of the extender, under the effect of the inflation pressure of the tire.

[0033] The axially inner end 10 of the extender comprises an internal reinforcing element 17 (preferably in the form of a cable winding) connected to the external reinforcing element 15 by a reinforcing layer (not shown in the figures) made of reinforcing yarns embedded in an elastomeric composition, and together with the reinforcing elements 15 and 17, forms an internal structure of the extender. Other external elastomeric layers surround the internal structure of the extender.

[0034] The assembly is done by arranging the extender 1 on the rim 3 and then mounting the tire 2 on the extender 1. Once the assembly is completed, the tire bead imposes a circumferential contraction of the extender 1.

[0035] The extender of the invention comprises several cavities 20 distributed around the circumference of a front face 30 of the axially external end 11, cavities 20 which are designed to cooperate with removable fixing means 35 for several adjacent inserts 40 fixed in the cavities 20. The inserts 40 of the extender of the figure 1 have a general spherical shape and the cavities 20 which receive them have a general spherical cap shape allowing the inserts 40 to fit into the cavities 20.

[0036] There figure 2 illustrates a partial front view of an extender 1 according to a first embodiment. figures 3, 4, 5 and 6present, in partial meridian section, different variants of the extender according to the first embodiment of the invention.

[0037] The extender 1 according to the first embodiment comprises inserts 40 fixed in a circumferential row of cavities 20, each cavity being provided with means for the removable fixing of each insert 40 inside a cavity 20. This results in a circumferential row of inserts 40 uniformly distributed around the circumference of the front face 30, which is a visible face of the extender 1, being spaced at a pitch "p" from each other ( Fig. 2 The means for removable attachment of the insert to the axially external end of the extender include means for attachment by reversible elastic interlocking of the inserts in the cavity or cavities of the axially external end of the extender. Preferably, the pitch p is greater than twice the diameter of the visible portion of the inserts 40.

[0038] In the variant of figures 1 and 3 The cavity 20 has a generally spherical shape and is designed to receive a spherical insert 40 or ball, preferably with a diameter between 3 and 5 mm. Even more preferably, a ball with the largest possible diameter allowed by the available space is chosen, as this ensures a better interface with the cavity, and therefore better retention of the insert, while also providing a sufficiently visible protruding portion. The depth of a cavity 20 is less than its diameter but greater than its radius, which ensures a secure fit of the insert 40 within the cavity 20, while allowing it to have a protruding portion relative to the flat surface of the front face 30, and therefore be visible. As an example, the spherical insert 40 of the figure 3 has a diameter of 3 mm and protrudes approximately 0.6 mm from the flat surface of the front face 30.

[0039] THE figures 4, 5 and 6They illustrate cavities 20 made to cooperate with inserts 40 having removable hook-type fastening means 35, thus allowing reversible elastic clipping of each insert 40 into a cavity 20. An insert 40 according to these variants is a part of revolution having a head 41, which is the part with the largest cross-section and is connected to a fastening base 43 by a rod 42. The fastening base 43 has a frustoconical end 44 forming a hook and securing the insert inside a cavity 20. By way of example, the head 41 may have a diameter of 5 mm, the rod 42 a diameter of 2 mm, and the fastening base 43 an end forming the small base of the cone of 2.4 mm extended forwards by a wall inclined at approximately 15°.

[0040] The mounting bases for the 40 inserts figures 4 to 6are identical, these inserts differing from each other primarily in the shape and dimensions of their head 41. Thus, the head 41 of the insert of the figure 4 is very protruding, it is shaped like a hemisphere. The head 41 of the insert of the figure 5 is flatter than the previous one; it has the shape of a spherical cap protruding with its edges from the surface of the front face 30. The head 41 of the insert of the figure 6 also has a spherical cap shape like that of the figure 5 , but it is less protruding than this one, having the edges buried below the surface of the front face 30. The depth h of an insert 40 is preferably greater than its radius d / 2 and less than its diameter d, where d is the maximum diameter of the insert and h is the burial depth of the insert measured from the surface of the front face 30.

[0041] The cavities 20 are made so that their radially outer end 22 ( Fig. 3 ) either located radially and / or axially recessed ( Fig. 11 ) relative to the radially outer end 34 of the axially outer end 11 of the extender. In the example of the figures 2 to 6 The axially external end of the extender 1 includes a chamfer 33 designed for this purpose. This facilitates mounting the tire onto the extender, while preventing the inserts 40 from being pulled out during this operation. In another variant (not shown), the radially external end 34 is provided with a protective bead (or protrusion) for the inserts, protruding further than the most prominent part of the inserts when they are fixed in the cavities provided for this purpose in the extender.

[0042] THE figures 7 and 8illustrate an extender 1 according to a second embodiment of the invention. The extender 1 comprises two coaxial rows of cavities 20 in which the inserts 40 are fixed. The cavities 20 adjacent to the two rows may be located in the same radial direction, at both ends of the front face 30 ( Fig. 8 ). In another variant, as illustrated in the figure 7The cavities 20 of one row are staggered relative to the cavities 20 of the adjacent row (it is understood that the centers of the cavities in one row are angularly offset relative to the centers of the cavities in the adjacent row as seen in a front view of the extender), which allows for better distribution of the inserts on the front face 30 of the extender. Of course, a third row, or even several coaxial rows of cavities, could be considered, depending on the available space and the dimensions of the inserts 40. The removable fastening means are of the same type as those described with reference to the figures 1 to 6 .

[0043] THE figures 9 to 13illustrate variants of an extender 1 according to a third embodiment of the invention. The cavities 20 of the extender 1 are uniformly distributed around the circumference of the front face 30 in two coaxial rows of cavities. The cavities have a generally spherical shape to cooperate with removable spherical fastening means 35 for the inserts 40. An insert 40 according to this embodiment comprises a plate 42, generally flat on its upper face, visible on the front face 30 of the extender, and provided with removable fastening means on its lower face. The Figure 10 illustrates a variant of the extender comprising 40 inserts, each made in the form of an elongated flat plate equipped with two removable fixing bulbs (forming the removable fixing means for the inserts) with axes perpendicular to the plate at its ends. figure 11illustrates a variant in which the front face 30 of the axially external end 11 of the extender includes a cutout 25 into which the plate 42 of the insert 40 is fully inserted when it is brought, in the direction of the arrow illustrated in the figure, to be fixed in the cavities 20. The figure 12This illustrates another embodiment in which the plate 42 has a general equilateral triangular shape with three fixing bulbs (or spheres) in three corresponding spherical cavities 20 of the extender 1. After fixing the inserts, a gap "i" is thus formed between two plates 42 and two adjacent inserts 40, this gap being made of an elastomeric material and therefore flexible. The dimensions of the gap i are chosen to be small enough to allow local deformation of the extender, while still giving the visual impression of a circle formed by the adjacent inserts. For example, the values ​​of the gap i are between 2 and 5 mm. The figure 13This illustrates another embodiment in which the plate 42 has a flat, arc-shaped form and includes several fixation bulbs in spherical cavities 20 of the extender 1. A gap i also exists between two adjacent plates 42 for the same reasons as in the previously described embodiments. The insert 40 is fixed by simple axial pressure on the front face 30 of the extender, in the direction of the arrows in the figure.

[0044] THE figures 14 to 19illustrate different variants of an extender according to a fourth embodiment of the invention. The cavities of the extender according to this embodiment are formed in the form of a plurality of grooves 50 uniformly distributed around the circumference of the front face 30, each forming a constant angle with a radial direction. The grooves 50 are spaced at a pitch p equal to or greater than the width of a groove as measured on its outermost axial surface. The grooves are inclined with respect to the radial direction, forming an angle of approximately 40° with it. In one variant (not illustrated), the grooves are arranged along the radial direction of the extender.

[0045] To ensure better retention of the insert 40 in a groove 50, the cross-section of the grooves 50 has a substantially dovetail shape. By substantially dovetail shape, we mean a dovetail section, as illustrated in the figure 15 , or T-shaped, as illustrated in the figure 17 or even in the shape of an arched T, as best seen at the figure 19 The inserts 40 have a generally elongated shape, they have the width of the groove 50 and a cross-section corresponding to that of the groove 50, as illustrated in Figures 16, 17 and 18 .

[0046] The grooves 50 have an open radially inner end 51 and a closed radially outer end 52. As best seen in the figure 17The outer end 52 of the groove 50 is located radially recessed by a distance "e" relative to the radially outer end 34 of the axially outer end 11 of the extender. As an example, the length of an insert 40 is approximately 10 mm, the distance d is approximately 4 to 5 mm, the width of the insert, and therefore of the upper part of the groove 50, is approximately 2 mm, and that of the fixing base (the width of the T or the base of the groove 50) is approximately 3.4 mm.

[0047] THE figures 20, 21 and 23 illustrate an extender 1 according to a fifth embodiment. The inserts 40 are of the "clip" type; they therefore have a flat, elongated portion 30', visible on the front face 30 of the extender, and two fixing tabs 30" in two parallel cavities 20 of corresponding shape. For better fixation, the end of each tab 30" has a hook shape 30"'.

[0048] There figure 23Figure 1 illustrates an extender according to a sixth embodiment of the invention. The front face 30 of the extender comprises a single circumferential cavity 20' whose cross-section allows for the removable attachment of several inserts 40. In this embodiment, the inserts 40 are spheres, press-fitted into the cavity 20', the inserts being connected to each other by a flexible link 49, thus forming a single piece that is easier to mount in the cavity 20', while allowing for local deformation of the extender accommodated at the level of the flexible links. In a variant of this embodiment, spherical indentations with a diameter comparable to that of the inserts and substantially different from the width of the cavity are formed around its periphery, allowing for better accommodating of spherical inserts.

[0049] The 40 inserts are preferably metallic, for example made of stainless steel. In one variant, they are made of a metallized plastic material. In another variant, they are made of a colored plastic material. In yet another variant, the upper face of the insert includes a letter or symbol or part of a letter or symbol (which allows, for example, several adjacent inserts to form a word or symbol, for example, the one representing the brand of the car on which the rolling assembly is mounted).

[0050] Of course, the solution of the invention offers the user the possibility of changing the design of the extender at any time by choosing the inserts he / she wants.

[0051] The invention is not limited to the embodiments described above.

[0052] Indeed, it will be possible to combine the different embodiments described above, in particular combining the means of fixing the inserts of the figures 4 to 6 to those of figures 7 to 13 .

[0053] The characteristics of the insert fixing methods can also be applied to the Figures 12 and 13 to other embodiments.

Claims

1. Expander for a rolling assembly of rotation axis X-X' comprising a tyre (2), having two beads (21) and a rim (3), the expander (100) being intended to provide the junction between one of the beads (21) and the rim (3), said expander (100) comprising an axially inner end (10), an axially outer end (11) and a body (12) oriented principally axially and arranged between said axially outer end (11) and said axially inner end (10), such that, when mounted within the assembly, said axially inner end (10) is intended to be immobilized on said rim by means of an inner reinforcing element (17), said axially outer end comprising an outer reinforcing element (15) is intended to receive a bead (21) of a tyre (2), characterized in that said axially outer end (11) includes a front face (30) provided with several cavities (20) distributed around the circumference thereof, said cavities being open on said face and formed so as to cooperate with means (35) for removably fastening several adjacent inserts (40).

2. Expander according to Claim 1, characterized in that said means (35) for removably fastening the insert (40) to the axially outer end (11) of the expander (1) comprise means for fastening the inserts (40) by reversible elastic engagement in the cavity (20') or the cavities (20) of the axially outer end (11) of the expander.

3. Expander according to one of Claims 1 and 2, characterized in that said cavity (20', 20) is formed so as to cooperate with spherical fastening means.

4. Expander according to one of Claims 1 and 2, characterized in that said cavity (20) is formed so as to cooperate with hook-shaped fastening means.

5. Expander according to one of the preceding claims, characterized in that it comprises at least one circumferential row of cavities (20).

6. Expander according to one of Claims 1 to 4, characterized in that it comprises two coaxial circumferential rows of cavities (20), the cavities of one row being offset angularly with respect to the cavities of the other row.

7. Expander according to one of the preceding claims, characterized in that said cavities are slots (50) uniformly distributed around the circumference of said front face.

8. Expander according to Claim 7, characterized in that the cross-section of said slots (50) is substantially dovetail-shaped.

9. Expander according to one of Claims 7 and 8, characterized in that said slots (50) have an open radially inner end (51) and a closed radially outer end (52).

10. Expander according to one of Claims 7 to 9, characterized in that said slots (50) are radial or each form a constant acute angle with the radial direction of the expander.

11. Expander according to one of the preceding claims, characterized in that the cavity or cavities are formed in such a way that the radially outer end (22) thereof is set back radially and / or axially with respect to the radially outer end (34) of the axially outer end (11) of the expander.

12. Insert (40) including removable fastening means (35) intended to cooperate with at least one of the cavities (20) of the expander (1) according to one of the preceding claims.

13. Insert according to Claim 12, characterized in that it includes a plate (42) provided with fastening means for fastening in at least two adjacent cavities (20).

14. Assembly including an expander (1) according to one of Claims 1 to 11 and several inserts (40) according to one of Claims 12 and 13.

15. Rolling assembly of rotation axis X-X' comprising a tyre (2), having two beads (21), a rim (3) and an expander (1) according to one of Claims 1 to 11 intended to provide the junction between one of the beads (21) and the rim (3), said expander being provided with inserts (40) according to one of Claims 12 and 13.