Method for manufacturing a conveyor or power transmission belt and associated mould

Abstract

The invention relates to a mould (1) for manufacturing a belt, comprising: - two end elements (8a, 8b) comprising at least one notch (9), such that the belt (2) comprises, at each of its longitudinal ends (5a, 5b), at least one tooth (10), the teeth (10) being complementary in order to interlock when the longitudinal ends (5a, 5b) of the belt (2) are joined; and - at least one mould pin (11) arranged so as to pass through the at least one tooth (10) at the neutral fibre plane of the belt (2). This mould comprises four retaining profiles (13) arranged perpendicular to the side plate (6a, 6b) and configured to hold a traction cable (12) extending between the two mould pins (11) in the neutral fibre plane of the belt (2) at a main zone (2a) of the belt (2).

Description

[0001] DESCRIPTION

[0002] Title: Manufacturing process for a conveyor or power transmission belt and associated mold

[0003] technical field

[0004] The present invention relates to a method for manufacturing a belt. In particular, the invention makes it possible to manufacture a belt with improved mechanical properties.

[0005] The invention finds a particularly advantageous application for the manufacture of conveyor belts, lifting belts, or power transmission belts.

[0006] Previous technique

[0007] Conveyor, lifting or power transmission belts, toothed or not, offer many advantages: they are economical, lightweight and quiet, they dampen vibrations, shocks and transmission jolts, they are clean and require no maintenance, thus saving time, they do not derail, and they also have a significantly longer lifespan than the classic chain transmission system, while offering similar mechanical performance to a chain.

[0008] The belts are commonly reinforced with tension cables made of steel, Kevlar®, carbon, fiberglass or similar materials.

[0009] Document WO2019 / 162455, filed by the applicant, proposes a power transmission belt with continuous cables and a link connecting the ends of the belt to form a closed loop. The presence of this link has the disadvantage of creating unevenness in the belt along its length, resulting in uneven wear over time. Furthermore, the link's weight can cause problems when the belt is used at high speeds. Finally, this belt, typically manufactured by molding, requires a different mold for each belt length.

[0010] Document EP2949965, also filed by the applicant, proposes a belt solution where the ends are welded to a central section. This weld creates a weak point on the belt, making it unsuitable for power transmission.

[0011] Description of the invention

[0012] The present invention aims to overcome these drawbacks by proposing a mold for manufacturing a conveyor or power transmission belt comprising:

[0013] - at least one side plate, configured to define a lateral edge of said belt,

[0014] - a lower plate and an upper plate, extending parallel to each other, and configured to define respectively the lower and upper faces of said belt,

[0015] - two end elements configured to each define a longitudinal end of the belt, each end element having a section comprising at least one notch, such that the belt has at each of its longitudinal ends at least one tooth, said teeth being complementary so as to interlock when the two longitudinal ends of the belt are joined, and

[0016] - at the slots of each end element, at least one mold shank arranged perpendicular to the side plate, said mold shank being arranged so as to pass through said at least one tooth at the plane of the neutral fiber of said belt.The mold according to the invention is particular in that it further comprises at least one retaining profile disposed against the lower plate in the vicinity of one of the end elements, one retaining profile disposed against the lower plate in the vicinity of the other end element, one retaining profile disposed against the upper plate in the vicinity of one of the end elements, and one retaining profile disposed against the upper plate in the vicinity of the other end element, said retaining profiles being disposed perpendicular to the side plate, said retaining profiles being configured to retain at least one cable forming a loop around the two mold rods and extending between the two mold rods in the plane of the neutral fiber of the belt at the level of a main area of ​​the belt extending between the retaining profiles.

[0017] Thanks to these features, a belt can be produced in which the tension cables are mostly aligned with the belt's neutral axis. When the belt is closed using a locking pin that passes through the loops of these cables, the locking pin is also aligned with the belt's neutral axis. This improves the belt's mechanical performance, making it suitable for applications such as high-speed power transmission. Furthermore, the mold allows for quick and easy belt manufacturing and offers flexibility in length, enabling the use of a single mold for different belt lengths.

[0018] At least the retaining profiles positioned against the upper plate can be configured to become an integral part of the belt after demolding. This avoids a discontinuity in the belt material at the location of these retaining profiles, thus preventing a point on the belt that would require reinforcement. Such a discontinuity adds steps to the belt manufacturing process and often fails to achieve satisfactory strength. The lower mold plate can be configured so that the belt has, on its underside, notches spaced at regular intervals to form a toothed face designed to mesh with toothed pulleys of a mechanical transmission. The lower plate has a retaining profile at each spacing between two notches of the belt. This provides a simple and effective means of implementing the invention in the manufacture of toothed belts.

[0019] For each mold rod, the distance between said mold rod and the nearest retaining profile to said mold rod can be less than or equal to said pitch, which avoids generating high local stiffness of the belt, and degrading its mechanical performance.

[0020] The mold may include a means for adjusting the gap between the end elements, which makes it possible to produce belts of different lengths using a single mold.

[0021] The retaining profiles arranged against the lower plate and / or the retaining profiles arranged against the upper plate can be formed from a single piece, extending along the mold, from one retaining profile to the other, which allows for easier and more precise placement of the retaining profiles when using the mold.

[0022] The present invention also relates to a method for manufacturing a conveyor or power transmission belt using a mold, according to the invention, said method comprising the following steps:

[0023] - installation of at least one traction cable in the mold, said traction cable forming at least one loop around two mold rods, each positioned at one of the end elements, so as to extend between said two mold rods, said traction cable being held, at a main area of ​​the belt extending between the retaining profiles, in the plane of the neutral fiber of the belt, by said retaining profiles,

[0024] - injection of a main material into the mold,

[0025] - belt removal from the mold.

[0026] Thanks to these features, a belt can be produced in which the tension cables are mostly aligned with the belt's neutral axis. When the belt is closed using a locking pin that passes through the loops of these cables, the locking pin is also aligned with the belt's neutral axis. This improves the belt's mechanical performance, making it suitable for applications such as high-speed power transmission. Furthermore, the mold allows for quick and easy belt manufacturing and offers flexibility in length, enabling the use of a single mold for different belt lengths.

[0027] During the demolding stage, at least two retaining profiles positioned against said top plate can be removed from the mold, and can be an integral part of the belt, which avoids having a discontinuity in the material of the belt at the location of these retaining profiles, and therefore a point of the belt to be reinforced, which adds steps to the manufacture of the belt, and often does not allow for satisfactory resistance to be obtained.

[0028] The said retaining profiles, which are an integral part of the belt, can be made of said main material, which is a simple and effective means of implementing the invention.

[0029] The manufacturing process may include the following steps after the demolding stage:

[0030] - transverse alignment of at least two teeth located at the two longitudinal ends of said belt, and

[0031] - insertion of a locking rod inside said at least two loops located in said at least two teeth to assemble the two longitudinal ends of the belt and form a closed belt, which makes it possible to obtain a closed belt whose mechanical resistance is improved.

[0032] After the main material has hardened, before the demolding stage, the process may include the following steps:

[0033] - opening of the mold to include a textile on the lower and / or upper surface of said belt,

[0034] - applying pressure and / or heating the mold, in order to fix said textiles to the main material of the belt, which makes it possible to give certain properties to the surfaces of the belt and / or to modify its aesthetics and / or to reinforce its resistance.

[0035] The present invention further relates to a method for manufacturing a plurality of secondary belts from a primary belt, comprising the following steps:

[0036] - manufacturing of said primary belt according to the invention, said primary belt comprising at least one longitudinal channel without a traction core,

[0037] - cutting said primary belt at the level of said at least one longitudinal channel into a plurality of secondary belts.

[0038] Thanks to these provisions, several belts with the advantages detailed above can be manufactured quickly, in a reduced number of manufacturing steps.

[0039] Brief description of the drawings The present invention and its advantages will become clearer from the following description of several embodiments given by way of non-limiting examples, with reference to the accompanying drawings, in which:

[0040] [Fig 1] Fig. 1 is a top view of a mold according to a first embodiment of the invention,

[0041] [Fig 2] Fig. 2 is a side view of the mold in Figure 1,

[0042] [Fig 3] Fig. 3 is an enlarged view of a detail from figure 2,

[0043] [Fig. 4] Fig. 4 is a top view of a belt manufactured by a manufacturing process corresponding to a preferred embodiment of the invention, [Fig. 5] Fig. 5 is a side view of the belt of Figure 4,

[0044] [Fig 6] Fig. 6 is an enlarged view of a detail from figure 5,

[0045] [Fig 7] Fig. 7 is a perspective view of the belt in Figure 4,

[0046] [Fig. 8] Fig. 8 is a perspective view of the longitudinal ends of the belt of Figure 4, assembled together to form a closed belt, and [Fig. 9] Fig. 9 is a side view of a mold according to a second embodiment of the invention,

[0047] Description of the implementation methods

[0048] In the illustrated embodiments, identical elements or parts bear the same reference numbers. Furthermore, terms with a relative meaning, such as vertical, horizontal, right, left, front, back, above, below, etc., should be interpreted under normal conditions of use of the invention, as shown in the figures. The X, Y, and Z axes are defined by an orthonormal coordinate system illustrated in Figure 1. Moreover, the geometric positions indicated in the description and claims, such as "perpendicular," "parallel," and "symmetrical," are not limited to the strict geometric sense but extend to geometric positions that are close, that is, that allow a certain tolerance within the technical field considered, without affecting the result obtained.This tolerance is notably introduced by the adverb "sensible", without this term necessarily being repeated before each adjective.

[0049] With reference to the figures, the mold 1 according to the invention makes it possible to manufacture a conveyor belt 2 or a power transmission belt.

[0050] The circumference of the belt 2, illustrated by way of example in Figures 4 to 8, comprises two opposite faces, including a lower face 3a and an upper face 3b, connected by two longitudinal edges, including a first lateral edge 4a and a second lateral edge 4b. The belt 2 also comprises two longitudinal ends 5a, 5b, which can be joined together to form a closed belt 2.

[0051] The main material of belt 2 can be chosen from thermoplastic materials and, by way of non-limiting example, polyurethanes (TPU or PU), polyethylenes, polyesters, or even rubber (for example, EPDM for Ethylene Propylene Diene Monomer, or CR for chloroprene), which combine the elastic properties of elastomers and the mechanical properties of plastics.

[0052] The mold 1 includes at least one side plate 6a, optionally two side plates 6a, 6b, parallel to each other, and whose dimensions and shape are configured to define the side edges 4a, 4b of the belt 2. The side plates 6a, 6b are in figure 1 perpendicular to the X axis.

[0053] Mold 1 also includes a lower plate 7a and an upper plate 7b, whose dimensions and shape are configured to define the lower face 3a and upper face 3b of belt 2. The lower plate 7a and upper plate 7b are parallel to each other and perpendicular to the side plates 6a, 6b. In Figure 1, the lower plate 7a and upper plate 7b are perpendicular to the Z-axis. Mold 1 further includes two end elements 8a, 8b, whose dimensions and shape are configured to define the longitudinal ends 5a, 5b of belt 2. The end elements 8a, 8b are not planar, but extend primarily in a plane perpendicular to the side plates 6a, 6b, 7a, 7b, that is, in Figure 1, in a plane perpendicular to the Y-axis.

[0054] The end elements 8a, 8b have a cross-section with at least one notch 9. The notches 9 form teeth 10 at the longitudinal ends 5a, 5b of the belt 2. The teeth 10 at the two longitudinal ends 5a, 5b have complementary shapes, so that the teeth 10 at the longitudinal ends 5a, 5b can interlock when the two longitudinal ends 5a, 5b are joined together to form a closed belt 2 with continuous material on its lower face 3a and upper face 3b. This interlocking is illustrated as an example in Figure 8.

[0055] The mold 1 further includes, at each end element 8a, 8b, and more precisely at the slots 9, at least one mold rod 11. The mold rod 11 is positioned perpendicular to the side plates 6a, 6b, that is, along the X-axis. The mold rod 11 is positioned so that, during the formation of the belt 2 in the mold 1, the mold rod 1 passes through the teeth 10 of the belt 2 formed by the slots 9 of the end elements 5a, 5b. Moreover, and for reasons explained below, the mold rod 11 is positioned so as to lie in the plane of the neutral axis of the belt 2. Since the mold rod 11 is a physical object, it naturally has a thickness and cannot, strictly speaking, be inscribed in a geometric plane.For the purposes of this invention, the expression "the mold rod 11 is arranged in a plane" means that the mold rod 11 extends primarily along this plane, and very slightly around this plane, over a distance equal to the diameter of the mold rod 11. The role of the mold rods 11 is to hold one or more traction cables 12 in the mold 1 before the injection of the main material of the belt 2. The traction cable 12 forms loops around the mold rods 11 arranged at the ends of the mold 1, and is thus positioned in the position it will occupy in the belt 2. Preferably, the traction cable 12 is arranged to form a loop at each of the teeth 10 of the belt 2.

[0056] 12-inch traction cables can be made of steel, Kevlar, or materials offering better mechanical properties such as Vectran or Zylon.

[0057] In the example shown in Figures 1 and 4, a single tension cable 12 runs across the entire width of the belt 2, moving back and forth from one end of the belt 2 to the other. This has the advantage of simplifying the tension adjustment of the tension cable 12. In other embodiments, several tension cables 12 can be used in a single belt.

[0058] Before or after demolding, the mold pins 11 are preferably removed from the teeth 10 of the belt 2, the loops formed by the tension cable 12 being held in place by the material of the teeth 10. The space previously occupied by the mold pins 11 can then be occupied by a belt locking pin, which can pass through the loops of the teeth 10 at both longitudinal ends 5a, 5b of the belt 2 after the teeth 10 at both longitudinal ends 5a, 5b have interlocked with each other. The locking pin is thus located at the plane of the neutral axis of the belt 2, which allows for good mechanical performance, particularly relevant for a power transmission belt intended for use at high speeds.

[0059] The mold 1 further comprises at least four retaining profiles 13, of which at least two retaining profiles 13 are arranged against the lower plate 7a, and at least two retaining profiles 13 are arranged against the upper plate 7b. The retaining profiles 13 extend primarily in a direction perpendicular to the side plates 6a, 6b, i.e., along the X-axis of Figure 1. The retaining profiles 13 preferably extend over the entire width of the lower plate 7a, or of the upper plate 7b respectively, along the X-axis. Of the two retaining profiles 13 arranged against the lower plate 7a, one retaining profile 13 is positioned near a first end element 8a, and the other retaining profile 13 is positioned near a second end element 8b.Similarly, on the two retaining profiles 13 arranged against the upper plate 7b, one retaining profile 13 is positioned near a first end element 8a, and the other retaining profile 13 is positioned near a second end element 8b. In this way, the retaining profiles 13 are able to hold, at a main area 2a of the belt 2, located between two end areas 2b of the belt 2, at least one cable 12 extending between the two stems of the mold 11 in the plane of the neutral axis of the belt 2, as illustrated in Figure 5. The end areas 2b of the belt 2 are therefore the areas located between the retaining profiles 13 and the longitudinal end 5a, 5b of the belt 2 closest to the retaining profile 13.In the case where more than two retaining profiles 13 are arranged against the lower plate 7a or against the lower plate 7b, the two retaining profiles 13 located closest to the longitudinal ends 5a, 5b are to be considered for defining the main zone 2a and the end zone 2b of the belt 2. In the case where the retaining profile 13 arranged against the lower plate 7a closest to a longitudinal end 5a, 5b is located at a different distance from this longitudinal end 5a, 5b than the distance separating the retaining profile 13 arranged against the upper plate 7b closest to this longitudinal end 5a, 5b, the retaining profile 13 located at a greater distance from the longitudinal end 5a, 5b is to be considered for defining the main zone 2a and the end zone 2b of the belt 2.For example, in the embodiment illustrated in Figure 3, the end zone 2b extends from the retaining profile 13 disposed against the upper plate 7b, the retaining profile 13 disposed against the lower plate 7a being closer to the longitudinal end 5a.

[0060] Thus the mold 1 has at least four retaining profiles 13: a retaining profile 13 against the lower plate 7a and a profile 13 against the lower plate 7b, near each of the end elements 8a, 8b of the mold 1. The proximity of the ends allows the traction cable 12 to be in the plane of the neutral fiber of the belt 2 over the greatest possible length.

[0061] The two retaining profiles 13 positioned against the lower plate 7a and / or against the upper plate 7b, respectively, can be separate parts, as illustrated in Figures 1 to 8. Alternatively, the two retaining profiles 13 positioned against the lower plate 7a and / or the two retaining profiles 13 positioned against the upper plate 7b can be made as a single part. Figure 9 illustrates, by way of example, an embodiment in which the two retaining profiles 13 positioned against the upper plate 7b are part of the same piece. The two retaining profiles 13 can then form the two ends of the part, and the part extends along the entire length of the mold between the two retaining profiles.

[0062] The retaining profiles 13 ensure that, at the main area 2a of the belt 2, which covers most of the length of the belt 2, the traction cable(s) 12 are in the plane of the neutral fiber of the belt 2. For the purposes of the present invention, the expression "the traction cable 12 is arranged in a plane" means that the traction cable 12 extends mainly along this plane, and very slightly around this plane, over a distance equal to the diameter of the traction cable 12.

[0063] It therefore appears that the retaining profiles 13 should be positioned as close as possible to the end elements 8a, 8b of the mold. In the case of a toothed belt 2, as described below, the distance between the retaining profile 12 and the locking rod 11 is preferably less than or equal to the pitch of the belt 2, the pitch being, for example, between 2 and 20 mm. However, there is a limit imposed by the flow of the main material of the belt 2 into the mold. Indeed, if the retaining profile 13 is located too close to the mold rod 11, the cable 12 forms too sharp an angle between the main area 2a and the end area 2b of the belt. It is therefore preferable to establish a minimum distance between the mold rod 11 and the main area 2a of the belt 2.

[0064] In a preferred embodiment, at least two retaining profiles 13, for example, the retaining profiles 13 positioned against the upper plate 7b, are configured to form an integral part of the belt 2. To achieve this, these retaining profiles 13 are made of a compatible material, or the same material, as the main material of the belt 2 that will be injected into the mold 1. Furthermore, these retaining profiles 13 are held relative to the rest of the mold 1 in such a way that they can be easily separated from the rest of the mold 1 during demolding. For example, they can be held in place between the lower plate 7a, or upper plate 7b respectively, and the tension cable(s) 12, which can perform this function by virtue of their tension. Alternatively, a temporary adhesive can be used to bond the retaining profiles 13 to the rest of the mold 1.Integrating the retaining profiles 13 into the belt 2 avoids any discontinuity in the surface of the belt 2 at their location. Furthermore, this allows the mold 1 to be used for different lengths of belt 2, as the retaining profiles 13 can be positioned within the mold 1 at different levels of the plates, and different retaining profiles 13 of varying shapes can be used depending on the type of belt 2 being manufactured.

[0065] It is also possible, within the scope of the present invention, for the retaining profile 13 to remain attached to the mold 1 after the belt 2 has been demolded. In this case, it is, for example, a metal part, or it can be formed by machining in the lower plate 7a and / or upper plate 7b. In this case, after demolding, a hole remains in the surface of the belt 2, creating a weak point where the transmission cable 12 is exposed. This hole can be filled by adding material, preferably of the same type as the main material, and this filler material can be covered, along with the rest of the belt, by a layer of textile. The filler material can then be fused with the rest of the belt during the textile fixing step, in which the mold is heated and / or pressurized.

[0066] The retaining profile 13 preferably has a constant section over its entire length, which can for example be parallelepiped or triangular in shape, with a larger surface for attaching to the lower plate 7a, or upper plate 7b respectively, or even rectangular.

[0067] In the embodiment illustrated in the figures, the mold 1 is configured to manufacture a belt having, on its lower face 3a, notches 14 spaced at regular intervals to form a toothed face arranged to mesh with toothed pulleys of a mechanical transmission. In this case, as illustrated in Figure 3, the lower plate 7a may have, at each spacing between two notches of the belt 2, a retaining profile 13. These retaining profiles 13 are therefore an integral part of the mold 1 and are not intended to be integrated into the belt 2. The presence of retaining profiles 13 at each spacing between two notches allows the lower plate 7a to be used to manufacture different belt lengths, as will be explained below.

[0068] The mold 1 preferably includes a means for adjusting the gap between the end elements 8a, 8b. For example, as illustrated in Figure 1, one of the end elements 8b can be translationally movable along the side plates 6a, 6b, and lower and upper plates 7a and 7b, along the Y-axis, for example, via a rail system. Thus, a single mold 1 can be used to manufacture belts 2 of different lengths. These arrangements are particularly advantageous when the retaining devices 13 are also configured to be compatible with different belt lengths, for example, when they are, as described above, intended to be an integral part of the belt 2 and / or arranged along the entire length of the lower plate 7a.

[0069] In the example shown, the end element 8b is movable in translation relative to the lower plate 7a, which is configured to form the notches 14 of the belt 2. The end element 8b therefore has a shape corresponding to the notches 14 of the belt, conforming to the surface of the lower plate 7a. Adjusting the length of the belt 2 is thus possible in this case with a pitch equal to the pitch of the notches 14.

[0070] In the examples shown, the lower plate 7a is configured to form a serrated face, and the upper face 7b is flat. In other embodiments not shown, the mold 1 has flat lower plates 7a and upper plates 7b, and the retaining profiles 13 can all be designed to integrate the belt 2 after demolding.

[0071] The mold 1 preferably includes at least one inlet pouring groove 15a, through which the main material of the belt 2 is intended to be injected, and optionally an outlet pouring groove 15b, through which the excess main material can be discharged. The grooves 15a, 15b are preferably located in at least one of the lower 7a and / or upper 7b plates of the mold. The grooves 15a, 15b preferably extend along the longest dimension of the belt 2, i.e., along the Y-axis. After demolding, the main material that has solidified in the grooves 15a, 15b is preferably cut from the rest of the belt 2. The mold 1 thus makes it possible to manufacture a belt 2, when used in a manufacturing process comprising the following steps:

[0072] - installation of at least one traction cable 12 in the mold 1, said traction cable 12 forming at least one loop around two mold rods 11 each disposed at one of the end elements 8a, 8b, so as to extend between said two mold rods 11, said traction cable 12 being held, at the level of a main area 2a of the belt 2 extending between the retaining profiles 13, in the plane of the neutral fiber of the belt 2, by said retaining profiles 13,

[0073] - injection of a main material into mold 1,

[0074] - demolding of belt 2, some retaining profiles 13 can then be removed from mold 1 in order to become an integral part of belt 2.

[0075] Before demolding, one or more textiles can be applied to the belt 2. These textiles can reinforce the surface strength of the belt 2 or improve its appearance. To do this, after the main material has solidified, the mold 1 can be opened to insert the required textile layers. The mold 1 is then closed and may be subjected to pressure and / or heating. The temperature and / or pressure bond the textile to the main material.

[0076] After demolding, the teeth at the two longitudinal ends can be aligned transversely, i.e., interlocked to form a continuous closed belt. This assembly can then be locked by inserting a locking rod into the loops formed by the traction cable(s) 12.

[0077] The mold 1 according to the invention can be used to manufacture a plurality of secondary belts from a primary belt. The primary belt is then manufactured during a single mold operation cycle, and the secondary belts are produced by cutting the primary belt lengthwise, i.e., along the Y-axis. To do this, it is preferable to provide a longitudinal channel in the belt 2, at the point of the cut, free of the tension cable 12. The present invention is, of course, not limited to the embodiments described but extends to any modification and variant obvious to a person skilled in the art within the limits of the appended claims. Furthermore, the technical features of the various embodiments and variants mentioned above can be combined, in whole or in part.

Claims

Demands

1. Mold (1) for manufacturing a conveyor or power transmission belt (2) comprising: - at least one side plate (6a, 6b), configured to define a side edge (4a, 4b) of said belt (2), - a lower plate (7a) and an upper plate (7b), extending parallel to each other, and configured to define respectively the lower (3a) and upper (3b) surfaces of said belt (2), - two end elements (8a, 8b) configured to each define a longitudinal end (5a, 5b) of the belt (2), each end element (8a, 8b) having a section comprising at least one notch (9), such that the belt (2) has at each of its longitudinal ends (5a, 5b) at least one tooth (10), said teeth (10) being complementary so as to interlock when the two longitudinal ends (5a, 5b) of the belt (2) are joined, and- at the slots (9) of each end element (8a, 8b), at least one mold rod (11) disposed perpendicular to the side plate (6a, 6b), said mold rod (11) being disposed so as to pass through said at least one tooth (10) at the level of the plane of the neutral fiber of said belt (2), characterized in that it further comprises at least one retaining profile (13) disposed against the lower plate (7a) in the vicinity of one of the end elements (8a), one retaining profile (13) disposed against the lower plate (7a) in the vicinity of the other end element (8b), one retaining profile (13) disposed against the upper plate (7b) in the vicinity of one of the end elements (8a), and one retaining profile (13) disposed against the upper plate (7b) in the vicinity of the other end element (8b), said retaining profiles (13) being arranged perpendicular to the side plate (6a, 6b),said retaining profiles (13) being configured to retain at least one traction cable (12) forming a loop around the two mold rods (11) and extending between the two rods, mold (11) in the plane of the neutral fiber of the belt (2) at the level of a main area (2a) of the belt (2) extending between the retaining profiles (13).

2. Mold (1) according to claim 1, characterized in that at least the retaining profiles (13) arranged against the upper plate (7b) are configured to be an integral part of the belt (2) after demolding.

3. Mold (1) according to any one of claims 1 to 2, characterized in that said lower plate (7a) of the mold (1) is configured so that the belt (2) has, on its lower face (3a), notches (14) separated by a regular pitch to form a toothed face arranged to mesh with toothed pulleys of a mechanical transmission, said lower plate (7a) having, at each spacing between two notches (14) of the belt (2), a retaining profile (13).

4. Mold (1) according to claim 3, characterized in that for each mold rod (11), the distance between said mold rod (11) and the retaining profile (13) closest to said mold rod (11) is less than or equal to said pitch.

5. Mold (1) according to any one of claims 1 to 4, comprising a means for adjusting the gap between said end elements (8a, 8b).

6. Mold (1) according to any one of claims 1 to 5, characterized in that the retaining profiles (13) arranged against the lower plate (7a) and / or the retaining profiles (13) arranged against the upper plate (7b) are formed by a single piece, extending along the mold, from one retaining profile to the other.

7. A method for manufacturing a conveyor or power transmission belt (2) using a mold (1), according to one of the Claims 1 to 6, said method comprising the following steps: - installation of at least one traction cable (12) in the mold (1), said traction cable (12) forming at least one loop around two mold rods (11) each disposed at one of the end elements (8a, 8b), so as to extend between said two mold rods (12), said traction cable (12) being held, at a main area (2a) of the belt (2) extending between the retaining profiles (13), in the plane of the neutral fiber of the belt (2), by said retaining profiles (13), - injection of a main material into the mold (1), - belt demolding (2).

8. A manufacturing method according to claim 7, characterized in that during the demolding step, at least two retaining profiles (13) arranged against said upper plate (7b) are removed from the mold (1), and are an integral part of the belt (2).

9. A manufacturing method according to any one of claims 7 to 8, characterized in that said retaining profiles (13) forming an integral part of the belt (2) are made of said main material.

10. A manufacturing process according to any one of claims 7 to 9, comprising the following steps after the demolding step: - transverse alignment of at least two teeth (10) located at the two longitudinal ends (5a, 5b) of said belt (2), and - insertion of a locking rod inside said at least two loops located in said at least two teeth (10) to assemble the two longitudinal ends (5a, 5b) of the belt (2) and form a closed belt.

11. A manufacturing process according to any one of claims 7 to 10, characterized in that after hardening of the main material, before the step of Demolding, the process involves the following steps: - opening of the mold (1) in order to include a textile on the lower face (3a) and / or on the upper face (3b) of said belt (2), - putting under pressure and / or heating of the mold (1), in order to fix said textiles to the main material of the belt (2).

12. A method for manufacturing a plurality of secondary belts from a primary belt, comprising the following steps: - manufacturing said primary belt (2) according to any one of claims 7 to 11, said primary belt comprising at least one longitudinal channel without a traction core (12), - cutting of said primary belt (2) at the level of said at least one longitudinal channel into a plurality of secondary belts.

13. Conveying or power transmission belt (2) manufactured according to a manufacturing process according to any one of claims 7 to 12.

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