A reinforced bicycle tyre

Abstract

A bicycle tyre (1) comprising tyre carcass (10) defining a tyre interior space (20) for the inflation fluid and having opposite sidewalls (11, 12) and central wall (13) connecting the sidewalls (11, 12), the sidewalls (11, 12) defining a tyre base (40) configured for fastening to a bicycle rim; a tread (60) externally covering at least the central wall (13) of the tyre carcass (10); the bicycle tyre (1) comprises one or more 3D printed nets (70) embedded into the tyre carcass (10) by means of one or more vulcanization processes.

Description

[0001] Title: “A reinforced bicycle tyre”

[0002] DESCRIPTION

[0003] Field of the invention

[0004] The present disclosure relates to a bicycle tyre having a reinforced structure, according to the pre-characterization portion of claim 1.

[0005] More specifically the present disclosure relates to a reinforced bicycle tyre having a higher tearing and perforation resistance as well as a reduced weight with respect to known bicycle tyre.

[0006] Preferably, the present disclosure relates to a reinforced bicycle tyre having improved performance on carcass flexibility.

[0007] State of the art

[0008] Typically, a bicycle tyre comprises a carcass that forms a frame of the tyre and a tread part on a side of a ground contact surface between the ground and the carcass.

[0009] Since the bicycle tyres are required to be lightweight, to sustain light loads, they have a smaller thickness with respect, for example, to a tyre suitable for the automotive purposes.

[0010] Thus, the bicycle tyre where there are sharp objects such as nails, glass pieces, and / or metal pieces on the road, such sharp objects may easily penetrate the tread part reaching the carcass, causing damages or punctures.

[0011] Consequently, in order to mitigate such problems, the known bicycle tyres are provided with different reinforcements systems arranged in the tread and / or between the tread and carcass.

[0012] Such reinforcement systems comprise a more resistance rubber with thick tread.

[0013] In other cases, the reinforcement systems comprise cut-resistant fibre reinforcement, so that the tyre is protected against puncture.

[0014] However, the relatively stiff material or the weight of the reinforcement systems can have a negative influence on the performances of the bicycle tyre.

[0015] In further other embodiments, the reinforcement systems can comprise reinforcing ply made of multifilament threads of thermoplastic liquid crystal polyester filaments which increase the weight of bicycle tyre up to unacceptable level for using such a tyre in semi-professional or professional activities.

[0016] It is further to be noted that the reinforcing ply are arranged on the carcass. This specific positioning can cause problems during production as well as undesired behaviour of the tyre during its normal use.

[0017] In some other embodiments, layers of materials can be arranged on the carcass to improve some other performances of the tyre. For examples, in some embodiments, a 3D printed layer is provided and arranged onto the carcass by means of glue in order to provide structuring features (as disclosed in WO2023 / 043992 A1) or sound adsorbing and rigidity features (as disclosed in EP3778267 A1).

[0018] Summary of the invention

[0019] Therefore, the technical purpose of the present disclosure is to provide a bicycle tyre that can obviate the aforementioned prior art drawbacks.

[0020] In particular, the object of the present disclosure is to provide a bicycle tyre that can improve the tearing resistance without increasing the overall weight of the bicycle tyre as well as that can control the carcass flexibility.

[0021] It is further object of the present disclosure to provide an alternative way to improve the tearing resistance for a bicycle tyre without increasing the overall weight of the bicycle tyre as well as that can control the carcass flexibility. The aforementioned technical purposes are substantially fulfilled by a bicycle tyre that comprises the technical features as disclosed in one or more of the accompanying claims.

[0022] Advantages of the Invention

[0023] According to the present disclosure, using one or more 3D printed nets in the carcass allows to improve the puncture and tearing resistance without influencing the performance of the bicycle tyre itself.

[0024] Further, according to the present disclosure, using one or more 3D printed nets in the carcass allows to improve different aspects of the tyre controlling the pattern, string density and thickness of the 3D printed nets and preferably the shape. Namely it is possible to improve and control the carcass flexibility for both rolling performance and dynamic stability as well as it is possible improve the puncture resistance and resistance to tear propagation.

[0025] DESCRIPTION OF DRAWINGS

[0026] Further features and advantages of the present disclosure will result more clearly from the illustrative, non-limiting description of a preferred, non-exclusive embodiment of bicycle tyre as shown in the annexed drawings, in which:

[0027] - Figure 1 shows a perspective view of the portion of the bicycle tyre according to a first embodiment of the present disclosure with some parts exported to better show the others, wherein a portion of the coating of the carcass has been omitted in order to better show the 3D printed net embedded in a portion of carcass;

[0028] - Figure 2 shows a perspective view of the portion of the bicycle tyre according to a second embodiment of the present disclosure with some parts exported to better show the others, wherein a portion of the coating of the carcass has been omitted in order to better show the 3D printed net embedded in a portion of carcass; - Figure 3 shows a perspective view of the portion of the bicycle tyre according to a third embodiment of the present disclosure with some parts exported to better show the others, wherein a portion of the coating of the carcass has been omitted in order to better show the 3D printed net embedded in a portion of carcass;

[0029] - Figure 4 shows a perspective view of the portion of the bicycle tyre according to a fourth embodiment of the present disclosure with some parts exported to better show the others, wherein a portion of the coating of the carcass has been omitted in order to better show the 3D printed net embedded in a portion of carcass;

[0030] - Figure 5 shows schematic view of the transversal section of a string of the 3D printed net;

[0031] - Figure 6 shows schematic view of a first type of pattern of the transversal section of the 3D printed net;

[0032] - Figure 7 shows schematic view of a second type pattern of the transversal section of the 3D printed net;

[0033] - Figure 8 shows an enlargement of the framed area the of 3D printed net of Figure

[0034] 6;

[0035] - Figure 9 shows an enlargement of the framed area the of 3D printed net of Figure

[0036] 7;

[0037] - Figures 10-16 show a perspective view of the portion of the bicycle tyre according to different embodiments of the present disclosure with some parts exported to better show the others, wherein a portion of the coating of the carcass has been omitted in order to better show the 3D printed net embedded in a portion of carcass.

[0038] DETAILED DESCRIPTION Even when this is not expressly stated, the individual features as described with reference to the particular embodiments shall be intended as auxiliary to and / or interchangeable with other features described with reference to other exemplary embodiments.

[0039] In the following description the inventive features are described in connection with a so-called clincher tyre construction, but the same features can be applied also to a tubular tyre construction.

[0040] For the scope of the present description, a 3D printed net is intended as a net printed by means a 3D printer. Such 3D printed net can comprise mutually independent and / or mutually dependent strings.

[0041] The 3D printed net develops on a base printer plane on which it is printed and preferably is made in one-piece. Namely, as shown in figures 1-4, 14, 15, the 3D printed net comprises strings which branch out from ramification joints. In details, the strings of the 3D printed net lack weaving each other and mutual overlays. Alternatively, as shown in figures 10-13, the 3D printed net comprises independent strings without ramification joints, parallel each other's, equally spaced or not. Alternatively, as shown in figures 13 and 16, the 3D printed net comprises a combination of depended and independent strings with ramification joints in a portion and without ramification joints in a complementary portion.

[0042] Preferably, the 3D printed net can be made in one or more materials for example selected from polymeric, metallic, natural or their combination. More preferably, the material can be nylon, polyethylene, polyamide, polyethylene terephthalate, aramid or metal alloy.

[0043] It is worth noting that the strings of the 3D printed net can be manipulated by the intrinsic 3D printed process for obtaining a 3D printed net with specific mechanical properties.

[0044] According to the description, the 3D printed net as reported in the following, can be implemented in any pattern and shape available such as regular or irregular geometric shapes.

[0045] It is further to be noticed that the 3D printed net can have a surface area that can vary from a minimum size that can be produced to a maximum size compatible to the application in the carcass.

[0046] The 3D printed net has relative mechanical properties related to the flexibility, elasticity, tensile strength, ductility etc. Preferably, the 3D printed net allows to improve the tensile strength saving the other mechanical properties with respect to a tyre for the same application.

[0047] For the scope of the present description, a carcass is a component which defines and outlines the tyre interior space for an inflation fluid. Namely, the carcass is the casing for the inflation fluid.

[0048] The carcass is in the form of sheet which define the tyre interior space by warping around itself one or more times or by defining a single structure.

[0049] In the case of clincher tyre construction, the sheet can wrap around the relative beads and in the case of the of tubular tyre construction the sheet can wrap at the connecting end portions.

[0050] Referring now to the annexed figures, numeral 1 generally designates a bicycle tyre of the present disclosure.

[0051] The bicycle tyre 1 comprises a tyre carcass 10 which defines a tyre interior space

[0052] 20 for the inflation fluid. The tyre carcass 10 has an internal surface 10a faced to the tyre interior space 20 and an opposite external surface 10b.

[0053] The inflation fluid can be air, or mixture of fluid known to the skilled person in the art and therefore not described in detail.

[0054] The interior space 20 comprises an air chamber 21, figures 1 and 3, or an inflation area 22 as shown in figures 2 and 4

[0055] It is to be noted that the tyre carcass 10 can comprise a bicycle ring to be mounted on a relative bicycle rim.

[0056] The tyre carcass 10 has two opposite sidewalls 11, 12 and a central wall 13 connecting the sidewalls 11, 12.

[0057] It is to be noticed that the sidewalls 11, 12 defines the tyre base 40 configured for fastening to a bicycle rim.

[0058] The sidewalls 11, 12 and the central wall 13 define a substantially U-shaped empty ring or, alternatively, a O-shaped empty ring wherein opposite to the central wall 13 the tyre carcass 10 can be fastened to a bicycle rim.

[0059] In the clincher tyre construction, the sidewalls 11, 12 and the central wall 13 define a substantially U-shaped empty and the tyre carcass 10 has an opening 18 on the opposite to the central wall 13.

[0060] In the case of a tubular tyre construction, it shall be noted that the sidewalls 11, 12 and the central wall 13 define a closed chamber for the fluid. In fact, such empty ring can be filled with a fluid (such as air) in the air chamber 21 or directly in the inflation area 22 upon coupled with the bicycle rim.

[0061] In the case of the clincher tyre construction, each sidewall 11, 12 has a free end

[0062] 14, 15 which defines a head 16, 17. Each bead 16, 17 is a bend of the relative sidewall 11,

[0063] 12 at the free ends 14, 15. Irrespective of the embodiment (tubular tyre construction or clincher tyre construction), the tyre carcass 10 comprises a bead core 30 arranged inside each bead 16,

[0064] 17 of the free ends 14, 15 of the sidewalls 11, 12.

[0065] Each bead core 30 can be made of rigid and elastic material such as metal, for giving to the bicycle tyre 1 a base rigid structure.

[0066] The bead cores 30 run in the relative bead 16, 17 defining two rings.

[0067] In addition, the bead cores 30 inserted in the relative bead 16, 17 define a tyre base

[0068] 40 configured for fastening to a bicycle rim.

[0069] Namely, the tyre base 40 comprises retaining elements defined by the assembly of beads 16, 17 with the bead cores 30 configured to engage relative catching means formed to the bicycle rim to fix the bicycle tyre 1 to the bicycle rim and retain it during the use conditions of the bicycle tyre 1.

[0070] In the case of a tubular tyre construction, each sidewall 11, 12 has a connecting end portion configured to mutually connect the other connecting end portion. Each connecting end portion comprises a reinforcement bead and connecting elements configured to mutually connected the connecting end portions. In addition, the connecting end portions define a tyre base 40 configured for fastening to a bicycle rim such as by glue process.

[0071] The central wall 13 extends between two opposite perimetral edges 13a, 13b. Each sidewall 11, 12 instead extends from the relative perimetral edges 13a, 13b to the beads

[0072] 16, 17 or to the respective connecting end portions.

[0073] Irrespective of the embodiment (tubular tyre construction or clincher tyre construction), the tyre carcass 10 develops along a developing direction C-C that corresponds to a circumferential direction of tyre. The bicycle tyre 1 comprises a tread 60 externally covering at least the central wall

[0074] 13 of the tyre carcass 10.

[0075] It is to be noted that the tread 60 can be applied on the tyre carcass 10 by bonding or the tread 60 can embed at least a portion of the tyre carcass 10.

[0076] Namely, the tread 60 can be applied on an external surface of the tyre carcass 10 opposite to an internal surface faced to the interior space 20.

[0077] In the present embodiment, the tread 60, having a coupling surface facing the tyre carcass 10 and opposite environment surface normally faced to the external environment, is attached to the tyre carcass 10 by coupling of the external surface 10b of the tyre carcass

[0078] 10 and the coupling surface of the tread 60.

[0079] Such coupling can be performed by bond processes for example using glue.

[0080] In the case of embedding, the tyre carcass 10 is at least in part immersed in the tread 60 such that the relative external surface is arranged between the coupling surface and the environment surface, namely in the thickness of the tread 60 for example by means of vulcanization process.

[0081] In further embodiment, the tyre carcass 1 can comprise a reinforcement layer arranged between the tyre carcass 10 and the tread 60 to further improve the performance and resistance of the tyre.

[0082] Preferably, the tread 60 comprises a central cover 80 provided for ground contact and covering at least the central wall 13 of the tyre carcass 10.

[0083] Specifically, the central cover 80 extends on the central wall 13 between two opposite lateral edges 81, 82 and has a central cover thickness Tcc.

[0084] In details, the central cover 80 is arranged at the central wall 13 to covering it. The central cover 80 can have different patterns formed on the environment surface as a function of the bicycle tyre application such as mountain-bike or corsa speed.

[0085] According to one embodiment, the tread 60 comprises lateral covers 90, 100 extending from respective lateral edges 81, 82 to the beads 16, 17 or to the respective connecting end portions.

[0086] Specifically, each lateral cover 90, 100 is configured to cover a relative sidewall

[0087] 11, 12 of the tyre carcass 10.

[0088] In addition, the lateral cover 90, 100 as the central cover 80 has a lateral thickness

[0089] Tic.

[0090] It is to be noted that in the present embodiment, the lateral covers 90, 100 extends from the central cover 80 at the opposite lateral edges 81, 82 up to the beads 16, 17 or to the respective connecting end portions.

[0091] In this way, the lateral covers 90, 100 are configured to be coupled at the beads

[0092] 16, 17 with the bicycle rim or at the respective connecting end portions.

[0093] According to the present description, the bicycle tyre 1 comprises one or more 3D printed nets 70 embedded into the tyre carcass 10 by means of one or more vulcanization processes.

[0094] According to the preferred embodiments, the one or more 3D printed nets 70 are arranged in the sidewalls 11, 13 and / or in the central wall 13. According to alternative and combinable embodiment, the one or more 3D printed nets 70 are arranged in the carcass

[0095] 10 at the internal surface 10a or at the external surface 10b.

[0096] Preferably, the one or more 3D printed nets 70 are coated with polymer in order to define a part or the entire tyre carcass 10. In other words, the one or more 3D printed nets

[0097] 70 are coated inside with polymer so as to outline the tyre carcass.

[0098] According to the preferred embodiment, the one or more 3D printed nets 70 are arranged into the tyre carcass 10 by one or more vulcanization processes.

[0099] Thanks to the position of the 3D printed nets, i.e. into the carcass 10, the 3D printed net 70 improves the tearing resistance and puncture resistance of the bicycle tyre 1 assuring at the same time a weight substantial identical to a known bicycle tyre.

[0100] Furthermore, thanks to the position of the 3D printed net 70 is possible to prevent a tear or rip from becoming larger. Namely, the pattern of the 3D printed net 70 allows to stop the propagation of tear in the bicycle tyre 1.

[0101] In addition, the 3D printed net 70 is extremely durable because. This makes the bicycle tyre 1 resistant to tearing, ripping and fraying.

[0102] Furthermore, the 3D printed net 70 allow to improve the carcass flex as a function of the type of tyre improving rolling performance and dynamic stability.

[0103] It should be noted that the one or more 3D printed nets 70 are not arranged in the tread and / or between the tread and carcass.

[0104] It is to be noted that the tyre carcass 10 has a carcass thickness Tea.

[0105] Preferably, the one or more 3D printed nets 70 are arranged in the carcass thickness

[0106] Tea.

[0107] Each 3D printed net 70 applied in the tyre carcass 10 is embedded in the tyre carcass 10 to be part of the tyre carcass 10 structure.

[0108] Namely, each 3D printed net 70 is embedded, buried or immersed into the carcass thickness Tea, preferably by coating such as with rubber or other polymers in vulcanization process.

[0109] In details, each 3D printed net 70 is arranged inside the tyre carcass 10 such that a layer or film of tyre carcass 10 material, such the coating material, is arranged on each two opposite surfaces of the 3D printed net 70 and the coating material is distributed around the 3D printed net 70 to fill empty spaces.

[0110] In other words, the one or more 3D printed nets 70 are pieces of material inserted into the tyre carcass 10 which extend inside the tyre carcass 10 in one or more portions of the tyre carcass 10 or for the entire tyre carcass 10.

[0111] According to a preferred embodiment, the bicycle tyre 1 can comprise a plurality of 3D printed net 70 at least in part or totally overlapped one on the other inside the tyre carcass 10. Alternatively, or in combination, the bicycle tyre 1 can comprise a plurality of

[0112] 3D printed net 70 arranged side by side in the tyre carcass 10.

[0113] Each 3D printed net 70 of the plurality can be independent from the other in terms of material, extension, pattern and shape.

[0114] Alternatively, the one or more 3D printed net 70 can be coupled with the tyre carcass 10 by chemical bond processes for example using glue.

[0115] According to the preferred embodiments the 3D printed net 70 comprises a plurality of central strings 71 geometrically oriented along respective orientation directions A-A parallel to each other and / or transversal to each other converging on area connection points 70'. In addition, the 3D printed net 70 comprises a plurality of perimetral edge strings 72 defining a net area 73. Preferably, the perimetral edge strings

[0116] 72 delimits the net area 73.

[0117] It is to be noted that, at least a portion of the plurality of the central strings 71 are connected to the perimetral edge strings 72 at perimetral connection points 70”.

[0118] The 3D printed net 70 further comprises for each perimetral connection point 70” and for each area connection points 70' a ramification joint 74 from which the strings 71,

[0119] 72 of the plurality of strings 71,72 extend. Namely, the ramification joint 74 are identified as the respective perimetral connection points 70” and area connection points 70'. In details, the strings 71, 72 breach out from the ramification joint 74. In this way, the strings

[0120] 71, 72 do not overlay and / or weave each other.

[0121] It is to be noted that the 3D printed net 70 comprises empty spaces 78 between the strings 71, 72. Such empty spaces 78 as above reported are filled with material during embedding of the 3D printed net 70 into the carcass as the strings 71, 72 are surrounded by the same material.

[0122] Preferably, each string 71, 72 extends straight along the respective orientation direction A-A between two opposed end portions 71', 72', 71”, 72” wherein at least one end portion 71', 72', 71 ”, 72” start from a ramification joint 74. Namely, for the central strings 71 the relative end portions 71', 71” can correspond to end portions 71', 71” of central strings 71 starting from the same ramification joint 74 and / or the end portions 72',

[0123] 72” of the perimetral edge strings 72 starting from the same ramification joint 74. In addition, for the perimetral edge strings 72, the relative end portions 72', 72” can also correspond to the end portions 72', 72” of perimetral edge string 72 starting from the same ramification joint 74 as well as to the end portions 71', 71” of central strings 71 starting from the same ramification joint 74.

[0124] According to a preferred embodiment, each string 71, 72 has a string thickness Ts as the distance between two planes A and B tangent to opposed ends of a transversal section of a string 71, 72. It is to be noted that the transversal section of a string 71, 72 can be any shape preferably a circumference. In addition, the 3D printed net 70 has a string density as number of strings in a portion area 76 of the net area 73 and in the net area 73.

[0125] Namely, the string density is proportional to the number of strings 71, 72 in a portion area

[0126] 76 of the net area 73. For examples, in Figure 14 the string density in portion area 76 is greater than the string density in portion area 76 of Figure 15 as well as for Figure 10 and Figure 11. According to another examples, the string density in portion area 76 at the sidewall in figure 16 is greater than the string density in portion area 76 on the central wall in figure 1.

[0127] According to alternative embodiments of the 3D printed net 70:

[0128] - string density and the string thickness Ts are constant; or

[0129] - the string density varies and the string thickness Ts is constant; or

[0130] - the string density is constant and the string thickness Ts varies; or

[0131] - the string density and the string thickness Ts vary.

[0132] According to a preferred embodiment as for example shown in figures 6, 8, 10-13, the 3D printed net 70 defines with the plurality of strings 71, 72 a geometric pattern when the strings 71, 72 are oriented along the respective orientation directions A-A parallel to each other and / or transversal to each other defining substantially equal angles at ramification joints 73. It is to be noted that, the transversal orientation of the strings 71,

[0133] 72 in the geometrical pattern define a fixed number of strings 71, 72 branching out from the ramification joints 74 preferably as a function of position in the pattern. For examples, in figures 10-12 the geometric pattern has parallel central strings 71 and (not shown) peripheral edge strings 72 connected to the central strings 71. The central strings 71 can be oriented along the respective orientation direction A-A parallel to the developing direction C-C (circumferential direction) of the tyre or transversal to the to developing direction C-C of the tyre. In figure 13, the geometric pattern has parallel central strings 71 at the sidewalls 11, 12 and mutually transferal central strings 71 on the central wall 13 defining substantially equal angles at the ramification joints 73 at the central wall 13. The

[0134] 3D printed net pass from the parallel orientation to transversal orientation at lateral edges

[0135] 81, 82 in the above cited example but can be modified according to the performances to optimize.

[0136] According to a preferred embodiment as for example shown in figures 7, 9, 14, 15, the 3D printed net 70 defines with the plurality of strings 71, 72 a random pattern when the strings 71, 72 are oriented along the respective orientation directions A-A transversal to each other and defining substantially different angles at ramification joints 73. Namely, the central string 71 and the peripherical edge strings 72 are oriented along respective orientation directions A-A which defines different angles at the ramification joints 74 and a number of strings 71, 72 branching out for a ramification joint 74 that can change for each ramification joint 74. In the examples of figures 14 and 15, the random pattern is shown. Namely, the string thickness Ts of the 3D printed net of figure 15 is greater than the string thickness Ts of the 3D printed net of figure 14 and the string density of the 3D printed net of figure 14 is greater than the string density of the 3D printed net of figure 15.

[0137] According to a preferred embodiment as for examples shown in figure 16, the 3D printed net 70 defines with the plurality of strings 71, 72 a mixed pattern. The mixed pattern is a combination of one or more random patterns and one or more geometric pattern mutually connected along connection edges 77.

[0138] It is to be noted that the 3D printed net is printed and then put on the carcass 10 such that the net area 73 is arranged at the central wall 13 and / or on the sidewalls 11, 12 preassembling the tyre “green tyre”. Alternatively, the 3D printed net is directly printed on the carcass 10 top optimize the positioning. After the arrangement of the 3D printed net or a plurality of them, the one or more vulcanization processes are carried out for the embedding of the one o more 3D printed nets in the carcass.

[0139] According to one embodiment of the present invention, shown in figure 1, the 3D printed net 70 is embedded in the central wall 13 of the tyre carcass 10 at least between the sidewalls 11, 12. Namely, the 3D printed net 70 is arranged in the tyre carcass 10 between the perimetral edges 13a, 13b. In the present embodiment, the central cover 80 of the tread 60 is arranged on the central wall 13. In details, the 3D printed net 70 can extend in the tyre carcass between the perimetral edges 13a, 13b

[0140] According to one embodiment of the present invention shown for example in

[0141] Figure 3, the 3D printed net 70 is applied at least in part in each sidewall 11, 12 of the tyre carcass 10. Preferably, the sidewalls 11, 12 can be exposed to the external environment or covered by lateral cover 90, 100 of the tread 60. The 3D printed net 70 is arranged in the tyre carcass 10 for each sidewall 11, 12 at least between the perimetral edges 13a, 13b and the respective beads 16, 17 or between the perimetral edges 13a, 13b and the connecting end portions.

[0142] Namely, the 3D printed net 70 extends between the perimetral edges 13a, 13b and the beads 16, 17 or between the perimetral edges 13a, 13b and the connecting end portions respectively in the tyre carcass for each sidewall 11, 12.

[0143] According to one embodiment of the present invention, the 3D printed net 70 is applied at least in each sidewall 11, 12 and at least in part in the central wall 13.

[0144] Namely, each 3D printed net 70 can go beyond the perimetral edges 13a, 13b into the central wall 13 extending at least in part both into sidewalls 11, 12 and central wall

[0145] 13.

[0146] According to one embodiment, not shown in the figure, the 3D printed net 70 can extend between sidewalls 11, 12 as one-piece element.

[0147] According to an embodiment of the present disclosure as shown in figure 3, the tyre carcass 10 is made by the 3D printed net 70 such that the 3D printed net 70 is embedded into the sidewalls 11, 12 and into the sidewalls 11, 12. Namely, the tyre carcass 10 the central wall 13 and the sidewalls 11, 12 are made of 3D printed net 70 and define the frame / casing as above described.

[0148] In other words, the tyre carcass 10 corresponds to the 3D printed net 70 coated with the polymer. In this way, the 3D printed net 70 realizes a one piece sheet which outlines the tyre carcass 10.

[0149] Preferably, the sidewalls 11, 12 and central wall 13 of the tyre carcass 10 made of

[0150] 3D printed net 70, as previously embodiments, can be covered or embedded at least in part by / into the tread 60 at the sidewalls 11, 12 and / or at the central wall 13.

[0151] According to one embodiment of the present invention, shown in figure 4, the 3D printed net 70 is applied on the internal surface 10a of the carcass 10. Preferably, the 3D printed net 70 can extend between the beads 16, 17 or between the connecting end portions.

[0152] Namely, the 3D printed net 70 covers at least partially, preferably totally, the internal surface 10a of the carcass 10. In the present, embodiment, the 3D printed net 70 is embedded at the central wall 13 and on the sidewalls 11, 12.

[0153] Advantageously, the arrangement of the 3D printed net 70 on the internal surface

[0154] 10a provides further stretching and abrasion resistance, while still providing the core duty of reducing tear propagation for the vulcanized casing structure.

Claims

CLAIMS1. A bicycle tyre (1) comprising:- a tyre carcass (10) defining a tyre interior space (20) for an inflation fluid, said tyre carcass (10) having opposite sidewalls (11, 12) and a central wall (13) which connects the sidewalls (11, 12), said sidewalls (11, 12) defining a tyre base (40) configured for fastening to a bicycle rim;- a tread (60) externally covering at least the central wall (13) of the tyre carcass (10); characterized in that the bicycle tyre (1) comprises one or more 3D printed nets (70) embedded into the tyre carcass (10) by means of one or more vulcanization processes or covered at least in part by the tread (60) the central wall (13).

2. The bicycle tyre (1) according to claim 1, wherein 3D printed net (70) comprises:- a plurality of central strings (71) geometrically oriented along respective orientation directions (A-A) parallel to each other and / or transversal to each other converging on area connection points (70');- a plurality of perimetral edge strings (72) defining a net area (73), at least a portion of the plurality of the central strings () being connected to the perimetral edge strings (72) at perimetral connection points (70”);- a ramification joint (74) from which the strings (71,72) of the plurality of strings (71,72) extend for each perimetral connection point (70”) and for each area connection points(70').

3. The bicycle tyre (1) according to claim 2, wherein the 3D printed net (70) has:- each string (71,72) extends straight along the respective orientation direction (A-A)between two opposed end portions (71', 72', 71”, 72”), at least one end portion (71', 72',71”, 72”) starting from a ramification joint (74);- a string thickness (Ts) as the distance between two planes tangent to opposed ends of a transversal section of a string (71, 72).

4. The bicycle tyre (1) according to claim 3, wherein the 3D printed net (70) has a string density as number of strings in a portion area (76) of the net area (73) and in the net area(73) has:- the string density and the string thickness (Ts) are constant; or- the string density varies and the string thickness (Ts) is constant; or- the string density is constant and the string thickness (Ts) varies; or- the string density and the string thickness (Ts) vary.

5. The bicycle tyre (1) according to any claims 2 to 4, wherein the 3D printed net (70) defines with the plurality of strings (71, 72):- a geometric pattern when the strings (71, 72) are oriented along the respective orientation directions (A-A) parallel to each other and / or transversal to each other defining substantially equal angles at ramification joints (73);- a random pattern when the strings (71, 72) are oriented along the respective orientation directions (A-A) transversal to each other and defining substantially different angles at ramification joints (73);- mixed pattern when 3D printed net (70) has a combination of one or more random patterns and one or more geometric pattern mutually connected along connection edges(77).

6. The bicycle tyre (1) according to any claims claim 1 to 5, wherein the 3D printed net(70) is embedded in the central wall (13) of the tyre carcass (10) at least between the sidewalls (11, 12).

7. The bicycle tyre (1) according to any claims claim 1 to 5, wherein the 3D printed net(70) is embedded at least in part in each sidewall (11, 12) of the tyre carcass (10).

8. The bicycle tyre (1) according to any claims claim 1 to 5, wherein the 3D printed net(70) is embedded at least in part in each sidewall (11, 12) and at least in part in the central wall (13).

9. The bicycle tyre (1) according to any claims 1 to 5, wherein the tyre carcass (10) is made with the 3D printed net (70) such that the 3D printed net is embedded into the sidewalls (11, 12) and into the central wall (13).

10. The bicycle tyre (1) according to any claims claim 1 to 5, wherein the 3D printed net(70) is embedded on an internal surface (10a) of the carcass (10) facing the tyre interior space (20).

11. The bicycle tyre (1) according to any claims from 1 to 10, wherein the tyre carcass(10) has a carcass thickness (Tea), the 3D printed net (70) being embedded in the thickness(Tea) of the tyre carcass (10) by means of vulcanization process.

12. The bicycle tyre (1) according to any claims 1 to 11, wherein:- each sidewall (11, 12) has a free end (14, 15) which define a bead (16, 17);- a bead core (30) is arranged inside each bead (16, 17) of the free ends of the sidewalls(11, 12) and defines a tyre base (40) configured for fastening to a bicycle rim.

13. The bicycle tyre (1) according to any claims 1 to 11, wherein:- each sidewall (11, 12) has a connecting end portion configured to mutually connect the other connecting end portion;- the connecting end defines a tyre base (40) configured for fastening to a bicycle rim.

14. The bicycle tyre (1) according to any claims 1 to 13, wherein the 3D printed net is made of nylon, polyamide, metal alloy, polyethylene or aramid.

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