WO2011006865A1

WO2011006865A1 - Tyre fitted for attaching a functional member to the inner wall thereof and method for manufacturing same

Info

Publication number: WO2011006865A1
Application number: PCT/EP2010/059974
Authority: WO
Inventors: Jonathan Champredonde
Original assignee: Societe De Technologie Michelin; Michelin Recherche Et Technique S.A.
Priority date: 2009-07-15
Filing date: 2010-07-12
Publication date: 2011-01-20
Also published as: FR2948064A1; FR2948064B1

Abstract

The invention relates to a tyre comprising a crown, two sidewalls and two beads, of the type comprising on the surface thereof at least one area for attaching a member, in which the tyre includes, opposite said attachment area, a mounting base (20) made up of reinforcement fibres embedded in a rubber mixture. The tyre comprises a rubber mass, referred to as the inner liner (33), delimited by an inner surface in contact with the air inside the tyre, and an outer surface in contact with an adjacent rubber mass. Said tyre is such that the mounting base (20) is arranged at the interface between said inner liner (33) and the adjacent rubber mass.

Description

PNEUMATIC EQUIPPED FOR FIXING A FUNCTIONAL ORGAN TO ITS INTERNAL WALL AND METHOD OF MANUFACTURING THE SAME

FIELD OF THE INVENTION

The present invention relates to tires for vehicle wheels. It relates particularly to the attachment to pneumatic functional organs. Such members may be sensors, identification circuits, and / or bodies adapted to communicate with the tire environment, to monitor its operation and the evolution of its physical characteristics or to provide alarms, all functions more or less developed to offer the so-called smart tire market. STATE OF THE TECHNICAL

One of the main problems to be solved is that of the installation and maintenance of the bodies in the tire for sometimes very long periods, can even run during the entire life of the tire, and this in conditions that preserve the physical and functional integrity of the tire and these members in a particularly severe environment, whether it be the periods of rolling or resting of the tire vehicle thus equipped.

US 6,244,104 discloses a solution for fixing such a member against the inner wall of a tire, with a fixed portion, placed against the tire wall during manufacture of the latter. The fixed part allows the subsequent positioning of a functional member, for example by gluing.

WO 03/070496 discloses a solution in which the inner wall of the tire is coated before firing a tongue of material whose surface is lined with loops, forming a part of a hook-and-loop fastener of the loop type and hooks. The other part of this fastener is furnished with hooks which are capable of engaging in the loops of the first piece when the two parts are brought together against each other, after the baking of the tire and before mounting it. on a rim. On the opposite side to the hooks of this second piece is fixed the organ to be installed inside of the tire cavity. According to the aforementioned document the member can be sandwiched between the coated faces of loops and hooks of the two parts to retain it in the chosen position of the inner wall. This solution, which uses a technique known for a long time to achieve the removable attachment of a member on a tire, for example by US Patent 3,260,294, has the advantage of allowing the organ to be recovered at any time when the tire is disassembled, either to replace it, or to reuse it at the end of life of the tire, or to exploit certain data concerning it.

[0005] It is known that the wall of the tire must be able to deform freely and without stress cyclically at each turn of the wheel. It is also subject to additional deformations to collect all the efforts and sometimes shocks resulting from its movement on uneven roads, or even filled with various obstacles, such as potholes, pebbles, curbs, etc.. The solutions presented in the two previously cited documents suffer from the defect of directly integrated components in the tire, namely an increase in rigidity in the area of attachment that may affect the durability of the fastener or the fixed member. The increased rigidity of the evoked solutions impairs the flexibility and the good deformability of the flanks in the fastening zone.

BRIEF DESCRIPTION OF THE INVENTION [0006] In view of these difficulties, the invention aims to achieve the fixation of a member in a tire using a simple, reliable, durable fastening method, which causes little disturbance to the operation of the tire for receiving it and the body to be fixed.

According to this object, the invention firstly provides a tire with a top, two sides and two beads, of the type having on its surface at least one fixing zone of a member. According to the invention, said tire comprises a fixing base disposed inside the wall of said tire facing said fixing zone and consisting of reinforcing fibers embedded in a rubber mix.

Thanks to these characteristics, it is possible to fix the organ in a removable manner or not in an internal location of the wall that has been previously designed and made for this purpose. These characteristics also make it possible to achieve a fastening which does not induce any significant increase in rigidity, both at the sidewalls of the tire and at the level of the fixed member, thus preventing any damage to the flexibility and to the good deformability of the flanks. in the fixing area. According to another advantageous embodiment, the reinforcing fibers of the attachment base are oriented substantially radially. Such an arrangement makes it possible at the same time to satisfy the requirements relating to the anchoring of the connecting elements, those related to the conformation of the bandage during its manufacture and those related to the mechanical stresses (in particular the requirements in relation to the bending of the flanks of the tire) during use of said tire. The fibers are advantageously oriented at an angle between a range of +/- 5 degrees with respect to the radial direction of the laying. This limited range has the advantage of not limiting the flexion of the flanks during taxiing. On the other hand, it allows to lay the fibers in a multitude of different arrangements, depending on the applications and technical requirements to meet. According to an advantageous embodiment, the density and the method of distribution of the reinforcing fibers in the fixing base allow a connecting element penetrating into the base to cooperate with at least one of said fibers.

According to a first embodiment, in the mounting base, the fibers are arranged in a plurality of layers, the fibers of the same layer being arranged semi-randomly while remaining in a + orientation range. / - 5 degrees.

According to a second variant, in the fixing base, the fibers are arranged in a plurality of layers, and the fibers of the same layer have a preferred direction of orientation, with an angular and / or lateral offset between the fibers of at least two of the layers. Thanks to such arrangements, the fibers of the different layers intersect at multiple points. Such a tight distribution of the fibers makes it possible to ensure that a connecting element such as a hook penetrating into the base can hook onto at least one fiber, thus providing a reliable and durable anchoring in the base. The fibers are substantially long, for example of a length ranging from 2 mm to several centimeters. The presence of such fibers according to this type of arrangement provides an anti-cracking effect - A - particularly effective, so that any cracks or cracks in the base can not spread.

For the attachment base, fibers selected from the group of glass fibers, aromatic fibers and carbon fibers are preferably used. According to another advantageous embodiment, the fiber reinforcing layer is provided on a surface at least substantially corresponding to the surface of the functional member.

According to yet another advantageous embodiment, the tire comprises a mass of rubber, called inner rubber, delimited by an inner surface in contact with the air inside the tire, and an outer surface in contact with a mass of rubber adjacent, said tire being such that the mounting base is disposed at the interface between said inner liner and said adjacent gum mass. Advantageously, the tire comprises a carcass reinforcement, generally toroidal in shape and anchored in the two beads, wherein the carcass reinforcement constitutes the adjacent mass of rubber. In a variant, the adjacent mass of rubber is an additional mass of rubber disposed between the inner liner and the carcass reinforcement of the tire.

The rubber mixture of the mounting base comprises a module elastomer preferably identical to that of the mixture constituting the inner liner. According to yet another embodiment, in the wall of the tire, facing said attachment zone, is disposed an electronic identification member, for example a transponder with passive radio frequency identification provided with two antennas forming a dipole. . This member has its largest dimension preferably oriented in the circumferential direction, or substantially perpendicular to the arrangement of the fibers in the base. Such a member can be used, for example, to identify the tire and to memorize the important information of the latter. According to a variant, the electronic identification member is arranged, relative to the attachment base, on the opposite side to the attachment zone. In this way, it is protected by the fixing area. The invention also provides an assembly consisting of a tire as previously described and connecting elements, wherein said connecting elements are of suitable shape to be able to penetrate into the wall of the tire and come to anchor in the mounting base. The connecting elements, or hooks, preferably have an elongated shape with a pointed end and comprise at least one anti-return element. The presence of the non-return elements allows the hooks to freely move in one direction in the direction of penetration. The extraction of the hooks is prevented by the anti-return elements which are blocked by the fibers during an effort to move in the direction of extraction. A hooking effect of said hooks in the fiber reinforcing layer is obtained.

According to an advantageous embodiment, the non-return element comprises an arm fixed substantially on the tip of the connecting element and oriented substantially opposite the tip forming with the axial body a lower alpha angle at 60 degrees and preferably below 30 degrees. The second end of said connecting elements is preferably surmounted by a locking head.

According to another aspect of the invention, there is provided a functional member for cooperating with an assembly as previously described, wherein said functional member has a substantially planar shape and is flexible. The flexibility of the functional body allows it on the one hand to be flexible enough not to be destroyed by the bending of the tire and on the other hand not to cause damage to the inner liner contributing to the propagation of cracks due to the fastening hooks.

Finally, the invention relates to the method or processes for manufacturing a tire equipped in accordance with the aspects that have just been mentioned. There is therefore provided a method for manufacturing a tire comprising a wall to which a functional member can be fixed in a service position by means of a fastener comprising a first part integral with the wall and a second part suitable for be mechanically coupled with the first part by connecting elements when bringing these two parts together against each other to maintain said member in the wall. According to the invention, during the green joining of the tire components, after the application of the layer of inner rubber, is deposited in the area provided for the implantation of the support at least one layer of reinforcing fibers embedded in a rubber mix, is then applied the other rubber layers constituting the tire, then the firing of the tire is carried out believed. Other features and advantages of the invention appear from the description given below with reference to the accompanying drawings which show, by way of non-limiting examples, embodiments of the body of the invention.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 very schematically shows an exploded wall of a tire equipped with a mounting base according to the invention;

Figure 2 shows a similar wall, wherein a functional member is fixed in accordance with the invention;

Figure 3 shows an elevational view of a connecting element in the form of a hook; [0025] Figure 4 schematically illustrates a bottom view of a functional member, in this case a printed circuit, placed on a base;

Figure 5 is a schematic representation of a cross section of a tire equipped with the base of attachment on the lower part of its sidewall;

Figure 6 shows schematically a cross section of a wall of a tire equipped with a fixing with penetrating hooks according to the invention;

Figures 7 and 8 show schematically examples of arrangement of the fibers inside the base;

Figure 9 schematically shows the orientation of an identification dipole with respect to the orientation of the reinforcing fibers embedded in the attachment base. DESCRIPΉON D ¹ A OUPL ultiple EXAMPLES realized TION

Figure 1 schematically shows an exploded portion of a wall of a tire in which the various constituent layers have been separated to facilitate their viewing. A fixing base 20 for fixing a functional member is thus provided. This example relates to a tire without a tube, and the wall defines an inflatable cavity 25, surrounded by the envelope. The wall is coated with an inner layer of rubber 33 to optimize its sealing to the inflation gas. Behind the layer of rubber 33 is disposed, directly or through one or more layers of rubber, a carcass ply 32 provided with reinforcing cords 36 arranged between two layers of calendering gum 37, and one or more layers of flank gum 31.

The mounting base 20 consists of a plurality of fibers 21 embedded in a matrix of rubber material based on butyl rubber. This matrix is preferably made with a composition similar to that of the inner gum layer 33. Rows of fibers are aligned, preferably in several layers, with the fibers substantially aligned radially, preferably in a range of angular positions comprised in a range not exceeding +/- 5 ° with respect to the radial direction. It can be glass fibers, carbon, aromatic fibers, etc. All the layers are not necessarily made of fibers of the same nature and / or of the same size and / or the same inter-fiber spacing. The fixing base is disposed against the adjacent layer, preferably the carcass ply 32, on a surface defined according to the size of the member to be fixed, for example a few square centimeters.

In the example of Figure 1, the base comprises three layers of fibers. These layers are preferably arranged in aligned alignments, angularly and / or laterally, so as to maximize the interactions between the fastening hooks and the fibers, during the fixation of an organ. According to various variants, the fiber layers may be provided at different spacings for each layer, always in order to maximize the interactions. The example of FIG. 1 also shows an electronic identification element 34, for example a passive radio frequency identification transponder provided with two dipole-forming antennas 35, disposed opposite the base, to the opposite of the inner liner, for example against the carcass ply 32. Such an arrangement allows for example to facilitate the identification of the envelope and the storage of the important information of the tire.

In order to reduce the static imbalance induced by the presence of the mounting base, one can consider distributing a plurality of bases around the envelope at positions allowing a good distribution of the mass. Figure 2 shows a functional member 12 fixed to a mounting base 20. This member is advantageously constituted by an electronic circuit, as shown in Figure 4. The body is traversed by a plurality of hooks 40 , placed substantially perpendicular to the face of the member intended to be in the vicinity of the base. The hooks are inserted into the attachment base so as to interfere through the fibers 21 of the base 20. The hooks are advantageously designed to facilitate their insertion, while preventing their removal, so as to ensure the durability of the fixation. Finally, the fixing being achieved by means of point attachment points distributed in the surface of the base, the stresses induced by the bending of the wall of the tire at this precise location are not or very little transmitted to the member 12 fixed. The fact of using a very flexible rubber mix for the anchoring zone makes it possible to ensure that the microcracks induced in the rubber mixture by its piercing by the hooks will be contained by the fibers which will prevent any tearing. Thus, the openings created in the inner liner are superficial and do not hinder the level of tightness of the envelope. This effective and safe fastening mode is particularly suitable for use with heavy vehicles and civil engineering vehicles.

Figure 3 allows to better visualize the specificities of the connecting elements. In this example, they are made in the form of hooks 40. An axial body 41, placed on a locking head 45 extends longitudinally and ends with a tip 42 sufficiently acute to allow penetration into the mounting base 20. A non-return member 43 has at least one arm 44 attached to the body 41 in the region of the tip 42 and extending substantially to the locking head 45 forming with the axis of the body an alpha angle less than 60 degrees and preferably less than 30 degrees. The non-return element 43 is designed in the manner of a hook to prevent the withdrawal of the hooks of the mounting base. The density of the fibers of the fastening zone is provided so as to optimize the probability that a non-return element is intercepted by at least one fiber in the case where a force acting in the direction of the expulsion of the hook is applied. The multiplication of the fibers on the one hand, and that of the hooks on the other hand, allows a double assurance of a perennial fixation. The locking head allows the hook to cooperate with the member 12.

In the example illustrated in Figure 4, the functional member 12 is a printed circuit, of polygonal shape. In this schematic representation, the electronic elements as well as any protection elements are not illustrated. The polygonal shape has the advantage of reducing the areas of stress concentrations. The printed circuit is traversed by holes 41 distributed around the periphery of the circuit according to an arrangement not interfering with the arrangement of the active areas of the circuit. The holes 41 are intended to be traversed by hooks 40 to fix the printed circuit to the mounting base of the tire. Since the unit resistance of a hook is small, it is useful to fix a number of them in order to support a member in the extreme mechanical conditions present in a tire. It is preferable to use a printed circuit of the flexible type which makes it possible, on the one hand, to be sufficiently flexible so as not to be destroyed by the bending of the tire and, on the other hand, not to cause damage to the inner liner by contributing to the crack propagation due to fastening hooks. For example, a material such as Kapton FPC produced by the manufacturer Dupont (registered trademark) gives good results. Moreover, this material provides excellent resistance to mechanical, climatic and chemical attack.

According to an advantageous variant, the functional member is advantageously arranged against an aramid fabric or fabric constituting a protective layer. This type of material is advantageously used because it is well adapted to withstand the severe environment prevailing in the pneumatic cavity, both in pressure and temperature, and this for periods that can cover several years, while providing good flexibility.

The circuit 12 used may perform one or more functions for so-called "intelligent" tire, namely first of all an active or passive communication function in response to an electrical, magnetic or wireless solicitation. It can also perform measurement functions in the environment, such as temperature and pressure, or more operational measurements concerning constraints that affect the tire, dynamic parameters such as accelerations. It can finally exercise, without this list is limiting, monitoring or alarm functions.

The hooks are made of steel and implanted in the functional member 12. Figure 5 is a schematic representation of a cross section of a tire 50 equipped with a mounting base 20. In this example, the base is integrated in the lower part of the sidewall, under the inner layer of rubber 33. FIG. 6 schematically represents a cross-section of a wall of a tire 50 equipped with a base 20 on which is attached a functional member 12 according to the invention. The fasteners 40 pass through the inner liner 33 to dock with the base 20. The attachment is reliable and durable due to the presence of fiber reinforcements within the base, providing a snap effect without risk of removal.

Figures 7 and 8 show schematically an example of arrangement of the fibers 21 inside the base 20: in Figure 7, the fibers are oriented semi-randomly while remaining in a range of orientation of +/- 5 degrees in each of the constituent layers of the mounting base. In FIG. 8, the fibers have a preferred direction of orientation in each layer but the orientation changes in each of the successive layers in the limit of +/- 5 degrees with respect to the radial direction.

Figure 9 schematically shows the orientation of an identification dipole with respect to the orientation of the reinforcing fibers 21 embedded in the mounting base. When the tire casing provided with a mounting base integrated into its structure is out of manufacture, it is sufficient, either before the tire is shipped from the place of manufacture, or when it is mounted on a rim. , to associate the desired functional body according to the applications provided for this tire. The assembly is made by application and direct pressure of the member 12 on the base to cause the engagement of hooks or harpoons 40 in the base. This last operation can be performed manually or mechanically.

The various modes of attachment here mentioned can be made directly in the top of the wall of the tire, under the tread. The member 12 may also be fixed in the sidewall of the tire. The member may finally be located in or near the lower zone of the tire.

According to its method of construction, the hooking provided by the hooks 40 is irreversible. It is therefore not possible to recover the functional organ after it has been put in place. If this should be the case, either after a period of operation for the purpose of exploiting data recorded in the functional unit, or during the dismantling of the tire or at the end of its life, for the purposes of analysis or reuse if necessary, it would then be possible to cut the hook 40 with a suitable tool or remove the locking heads 45 hooks that hold the printed circuit. To reposition the body against the base of attachment, a replacement of the hooks cut by hooks in good condition is then required.

Of course, the invention is not limited to the examples described and shown here and various modifications can be made without departing from the scope defined by the appended claims.

Claims

A tire with a top, two sides and two beads, of the type having on its surface at least one attachment zone of a member, characterized in that said tire comprises a fixing base (20) disposed inside the wall (30) of said tire facing said attachment zone and consisting of reinforcing fibers (21) embedded in a rubber mix.

2. A tire according to claim 1, wherein the reinforcing fibers (21) of the attachment base (20) are oriented substantially radially at an angle within a range of +/- 5 degrees with respect to the radial direction of the laying. .

A pneumatic tire according to any one of the preceding claims, wherein the density and method of distribution of the reinforcing fibers (21) in the attachment base (20) allows a connecting element (40) penetrating the base ( 20) to cooperate with at least one of said fibers (21).

4. A tire according to any one of claims 1 to 3, wherein in the mounting base, the fibers are arranged in a plurality of layers, the fibers of the same layer being arranged semi-randomly while remaining in a orientation range of +/- 5 degrees.

5. A tire according to any one of claims 1 to 3, wherein in the attachment base, the fibers are arranged in a plurality of layers, the fibers of the same layer having a preferred direction of orientation, with a shift angular and / or lateral between the fibers of at least two of the layers.

A tire according to any one of the preceding claims, wherein the fibers are selected from the group of glass fibers, aromatic fibers and carbon fibers.

7. A tire according to any one of the preceding claims, comprising a mass of rubber, called inner rubber (33), delimited by an inner surface in contact with the air inside the tire, and an outer surface in contact with a mass of rubber. adjacent rubber, said tire being such that the mounting base is disposed at the interface between said inner liner (33) and said adjacent mass of rubber.

8. A tire according to any one of the preceding claims, wherein the rubber mix of the mounting base (20) comprises a module elastomer identical to that of the mixture constituting the inner liner (33).

9. A tire according to any one of the preceding claims, in the wall of which, facing said attachment zone, is disposed an electronic identification member (34).

10. An assembly of a tire according to any one of the preceding claims and connecting elements (40), wherein said connecting elements are shaped to be able to penetrate into the wall of the tire and come to anchor in the mounting base.

An assembly according to claim 10, wherein said connecting members have an elongated axial body (41) with a first pointed end (42) and comprise at least one anti-return element (43).

12. The assembly of claim 11, wherein the non-return element (43) comprises an arm (44) fixed substantially to the tip (42) of the connecting element and oriented substantially opposite the tip ( 42) forming with the axial body (41) of the hook an angle alpha less than 60 degrees and preferably less than 30 degrees.

13. An assembly according to any one of claims 10 to 12, wherein the second end of said connecting elements is surmounted by a locking head (45).

14. An assembly according to any one of claims 10 to 13, further comprising a functional member (12) of substantially flat and flexible shape.

15. A method of manufacturing a tire having a wall (30) to which a functional member (12) can be fixed in a service position, said member being then fixed against a mounting base (20) using connecting elements (40) during the bringing together of these two parts against each other to maintain said functional member (12) against the wall, characterized in that during the green joining of the tire components, after the application of the inner layer of rubber (33), at least one layer of reinforcement fibers (21) embedded in a rubber mix is placed in the area intended for the implantation of the support, the other layers of rubber constitutive of the tire, then one operates the cooking of the green tire.