WO2024023352A1

WO2024023352A1 - Plate for joining two end portions of a conveyor belt, joining device comprising at least one such joining plate, and associated strip of joining plates

Info

Publication number: WO2024023352A1
Application number: PCT/EP2023/071099
Authority: WO
Inventors: Bernard Tavernier; Marie DUBUY; Frédéric GUILLEMET
Original assignee: Fp Business Invest
Priority date: 2022-07-29
Filing date: 2023-07-28
Publication date: 2024-02-01
Also published as: FR3138483A1

Abstract

The invention relates to a joining plate (4) for a joining device (1) of a conveyor belt (2) intended to connect two end portions (21, 22) of at least one conveyor belt (2), the joining plate (4) having an outer surface (S1) intended to be flush with a useful surface of the conveyor belt (2) in the joining position and an inner surface (S2) opposite the outer surface (S1) intended to at least partially cover the two end portions (21, 22) of the conveyor belt (2) in the joining position, the joining plate comprising: a body (45) made of flexible material, having an outer surface forming the outer surface (S1) of the joining plate (4); a reinforcement plate (11) having fastening through-holes rigidly attached to the body; and a plurality of inserts (6) each having a fastening opening associated with one of the fastening holes so as to surround a rim of the fastening hole associated with one side of the reinforcement plate (11) for receiving fastening means (5) for fastening the joining device (1) to the end portions (21, 22), each one of which inserts being at least partially embedded in the body (45); the joining plate (4) being characterised in that the body (45) at least partially covers the fastening openings of the inserts.

Description

Junction plate of two conveyor belt end portions, junction device comprising at least one such junction plate and associated strip of junction plates

TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates, in general, to the technical field of joining devices for conveyor belts intended to connect the ends of a conveyor belt. For the sake of simplification, the term conveyor belt will, by convention, in this description, have the meaning of both conveyor belt and belt.

[0002] The invention relates more specifically to a junction plate for connecting two portions of conveyor belt ends, in particular provided with a textile reinforcement, to a conveyor belt junction device comprising at least such a junction plate , and an associated strip of junction plates.

STATE OF PRIOR ART

Conveyor belts are known, also called conveyor belts, used to transport, or convey, different materials or different products, such as coal, ores, industrial or agricultural products. These conveyor belts consist of belts made of a reinforced elastomer, or of a reinforced synthetic material, of an appropriate length and width, the ends of which must be connected together, before assembly, or after assembly, on support and drive devices comprising return rollers and idle rollers. Often these devices also include tensioning members, intended to tighten the conveyor belt.

[0004] Until now different means have been used to effect this connection of the ends of the conveyor belts. [0005] Originally, and still today, vulcanization is used when the strip is made of a reinforced vulcanizable elastomer. After preparation work intended to create complementary profiles in each end which apply to each other when said ends are brought together, vulcanization is carried out with the addition of heat and pressure as is well known. A variation of vulcanization is cold bonding.

[0006] Another known means of connection consists of using staples in the general shape of a U, cut from metal strip, which staples comprise upper plates and lower plates connected by knuckles, these staples being fixed in two series straddling each of the ends of the conveyor belt to be connected, such that the knuckles protrude and those of one series can be nested between the knuckles of the other series, a connecting and articulation rod then being passed inside the interlocking knuckles so as to connect the two ends by forming a sort of hinge. The known means used to fix the clips on the conveyor belt ends consist of rod fixing means such as crampons, rivets and screws.

[0007] In the more recent past, junction devices have been proposed using flat connecting elements generally made of reinforced elastomer or reinforced synthetic material, arranged respectively on one side and on the other side of the conveyor belt ends. and fixed on said ends which are to be connected. Examples of such junction devices are given in patents EP-0827575-B1 and EP-1163459-B1. These devices comprise an upper junction plate and a lower junction plate, possibly connected by a central part. These lower and upper junction plates have a spacing suitable for engaging the respective end of a conveyor belt, bringing it approximately into abutment against the central part, or in the case where the junction device does not present any central part, against a spacer provided for this purpose during assembly, then removed later. In other words, these junction devices comprise two pairs of fixing wings facing each other, the ends of the conveyor belt being introduced respectively between two wings of the same pair. The lower and upper parts forming a junction plate are generally attached to the ends of the conveyor belt using rivets, spikes, crampons, screw-nut systems, or by cold gluing or flat vulcanization. of the wings against the outer flat surfaces of the conveyor belt engaged between the wings.

[0008] The junction devices are generally made of a flexible and elastic material, for example vulcanized rubber, or of a synthetic material, such as polyurethane, in which is embedded a reinforcement, generally textile, having extensibility in the longitudinal reference direction of the conveyor belt.

[0009] The extensibility of the reinforcements of this type of junction devices in the longitudinal direction of the conveyor belt is intended to allow the junction devices mounted on the conveyor belts to cross repeatedly, without wear or excessive fatigue which could cause rapid deterioration, the curved parts of the path of the conveyor belts, namely, the bypass of the drive rollers, the return rollers and the tension rollers. Indeed, during this operation the upper part of the junction devices undergoes a tensile force while their lower part (that is to say that oriented towards the exterior surface of the rollers) undergoes a compressive force, and, this , due to the difference in the path of these parts, these paths being directly proportional to the radius of curvature, which varies due to the thickness of the joining devices.

[0010] The constraints being very different between the lower and upper parts, and in order to further improve the wear resistance of these junction devices, the Applicant has improved its product in the past so as to give the upper part greater extensibility than that of the lower part. In this type of conveyor belt junction, the central part then evolved so as to be separated from the lower and upper plates, this to give way to the use of independent spacers used at the time of assembly against which the first of the ends of the conveyor belt which is placed in the junction, between the lower and upper plates, then these spacers are removed before installation of the second of the ends of the belt transporter. In fact, the joining devices were made by molding or injection and had an “H” structure whose lower and upper plates and the central part were formed in one piece. This required for their manufacture as many molds as thicknesses of conveyor belts encountered in the field, and these joining devices had to be manufactured, therefore, in very small series, which increased the cost price, during manufacturing, storage and distribution.

[0011] This problem, namely that of the multiplicity of molds and molded products having to cope with the varied thicknesses of conveyor belts, was resolved in particular by producing, as explained above, the joining devices in three distinct parts: a part constituting the left and right upper wings forming a single piece, a part constituting the left and right lower wings forming a single piece, and an intermediate part, corresponding to the central bar of the “H” profile, this intermediate part forming a spacer . In such a configuration, it becomes possible to manufacture the two lower and upper plates separately and each is configured so as to be adapted to the forces they undergo (compression/traction forces) and the associated constraints. For example, the lower plate is arranged to undergo passage without damage over drive rollers, return rollers and tension rollers, driving or returning the conveyor belt at the ends of which is mounted the junction device considered, the plate lower coming directly into contact with these belt drive members. The upper plate is in direct contact with the different materials or different products transported on the conveyor belt. Furthermore, the upper plate is also generally swept by scrapers.

[0012] In any case, extensibility has become a predominant characteristic in the design of such a junction plate with a view to obtaining a junction device that is sufficiently flexible and elastic to undergo passage over rollers of drive and on return rollers while being equipped with tensile strength making it able to withstand all the forces it undergoes without damage. These characteristics of extensibility and resistance to such efforts of the junction plate are provided both by the flexible and elastic material (vulcanized rubber, synthetic material such as polyurethane) forming the junction plate and by the reinforcement which is integrated into it offering both extensibility in the longitudinal direction of the conveyor belt and a resistance adapted to resist the greatest tensile forces undergone by the conveyor belt.

[0013] Despite the progress made concerning the extensibility of such a junction plate, the Applicant continues to develop its product in order to increase the flexibility and improve the dynamic behavior of a device. junction. It has been observed that the fixing means (such as screws or rivets) joining the junction plates have a significant impact on the rigidity of the junction plates, and more generally of the junction device. This constraint is all the more important in certain applications, such as for so-called heavily coated conveyor belts. Indeed, to improve the resistance to abrasion and increase the lifespan of the conveyor belt, it is known that a conveyor belt is configured so that the layer of flexible and elastic material covering above the reinforcement, for example a textile frame, is thicker than the layer of flexible and elastic material located under said frame. In other words, the reinforcement is not located centrally in the thickness of the belt but off-centered towards the face of the conveyor belt coming directly into contact with the drive members of the conveyor belt. For this type of application, the means for fixing the junction plates of a given junction device each pass through one of the junction plates, one of the end portions of the conveyor belt then the other of the plates junction. The length of the fixing elements is constrained by the thickness of the junction plates together with the end portion, in particular to ensure that the fixing means are housed correctly in the inserts incorporated at least partly in the upper plates and lower. The consequence of such a constraint is the presence of as many fixing interfaces as there are fixing elements on the exterior surfaces of the associated junction plate, interfaces representing zones which become conducive to the appearance of defects in the material of the joint plate, for example cracks. Furthermore, the mobility of the fixing means during the passage of return members of the conveyor belt implies a stress increased mechanics on the material of the upper junction plate which is also a source of premature wear.

STATEMENT OF THE INVENTION

[0014] The invention aims to remedy all or part of the drawbacks of the state of the art by proposing in particular a solution making it possible to improve the flexibility of the junction devices while further improving their structural strength to improve their service life. use, and thus further limit maintenance operations.

To do this, according to a first aspect of the invention, a junction plate is proposed for a conveyor belt junction device intended to connect two end portions of at least one conveyor belt, the junction plate having an exterior surface to be flush, that is to say level, with a useful surface of the conveyor belt in the junction position and an interior surface opposite the exterior surface, and intended to at least partially cover the two portions ends of the conveyor belt in the junction position, the junction plate comprising: a body of flexible material, having an outer surface forming the outer surface of the junction plate; a frame plate having through fixing holes, secured to the body; and a plurality of inserts embedded at least partly in the body and each having a fixing opening associated with one of the fixing holes so as to surround a rim of the associated fixing hole on one side of the plate. frame, to receive means for fixing the junction device with the end portions; the junction plate being remarkable in that the body covers at least partly the fixing openings of the inserts. [0016] Thanks to such a combination of characteristics, the junction plate is thus devoid of inserts and/or fixing elements in an upper part consisting only of the body of the junction plate, which gives it increased flexibility and better dynamic behavior, in particular when passing drive members and return members, such as rollers of a transport trolley or a conveyor. In this way, whatever the total thickness of the junction plate adapted to a specific junction operation, it is possible to limit the impact of the fixing elements on the flexibility of the junction. The length of the fixing elements of a junction device comprising such a junction plate thus being independent of the thickness of the junction plate, the rigidity of the junction plate can be limited.

According to one embodiment, the body has a minimum thickness measured between the exterior surface and the inserts, greater than or equal to a distance equal to a height of the associated inserts. Preferably, this minimum thickness is at least a few millimeters.

[0018] According to one embodiment, the junction plate has an exterior surface constituted by an exterior surface of the body and an interior surface opposite the exterior surface and constituted by an interior surface of the body and/or the reinforcement plate , the exterior surface and the interior surface being equidistant from each other on either side of a median plane of the junction plate, the reinforcement and the inserts being positioned on the interior side of the junction plate relative to the median plane, for example between the median plane and the interior surface.

[0019] The median plane of the junction plate delimits an upper half of the junction plate located on the side of the exterior surface of said junction plate relative to the median plane of a lower half of the junction plate located on the side of the interior surface of said junction plate relative to the median plane, the distance separating the exterior surface and the interior surface of the body delimiting a thickness of the junction plate. [0020] According to one embodiment, the reinforcement plate and the inserts are housed on the side of the lower half of the junction plate relative to the median plane, at least partly, or even entirely, in the lower half of the junction plate in relation to its thickness, on the inner surface side.

[0021] The thickness of the junction plate is therefore delimited by the distance between the exterior and interior surfaces of said plate. The lower half of the thickness here designates the “lower half” of the associated junction plate, and in particular of the body of the junction plate. On the contrary, the upper half of the junction plate, and in particular of the body of the junction plate, is located above the lower half.

[0022] Thanks to such a combination of characteristics, the junction plate is thus devoid of inserts and/or fixing elements in its upper half, further improving its extensibility in this area most stressed when passing the drive members. and referral bodies.

[0023] According to one embodiment, the reinforcing plate is housed in the body and extends at a constant distance from the exterior surface. The armature plate may be integrally seated within the body such that the interior surface of the joint plate consists simply of an interior surface of the body itself. Alternatively, the reinforcement plate can be positioned flush with the interior surface of the junction plate, which then consists of an interior surface of the junction plate, or even of the body as well.

According to one embodiment, the reinforcing plate is textile, that is to say it comprises, preferably consists of, at least one layer, or even a plurality of layers, of textile. The reinforcing plate, or reinforcement, thus forms a woven reinforcement improving the resistance of the junction plate to tensile forces.

[0025] According to one embodiment, the body is formed from an elastomeric material, preferably rubber, and has an extensibility of between 15% and 40%, preferably between 20% and 30%. According to one embodiment, the body of the junction plate has orifices extending from the interior surface of the body in the lower half of the junction plate, the orifices being configured to partially accommodate the fixing means . These orifices to the right of each of the inserts each open out at least on the side of the interior surface of the junction plate but they can remain located in the lower half of the plate. In this configuration, an upper part of the junction plate carrying the outer surface, preferably its upper half, can be devoid of orifices. This reduces the number of areas conducive to the appearance of defects, for example cracks. The dynamic behavior of the junction plate and of the entire device is thus improved.

[0027] According to one embodiment, the body of the junction plate comprises through orifices, extending from the exterior surface of the body of the junction plate towards the interior surface of the junction plate, the orifices being configured to each be crossed by one of the fixing means. Preferably, the through holes are cylindrical. Such through orifices are located to the right of each of the inserts and thus each provide a function of passageway for the fixing means towards the associated insert.

[0028] According to one embodiment, a diameter of each through orifice is configured so as to be strictly less than a diameter of the fixing openings of the associated insert so that the body partly covers said openings of fixing the inserts. Thanks to the elasticity of the material constituting the body of the junction plate, it appears that each orifice is configured to deform elastically during the passage or introduction of one of the fixing elements through it, the orifice associated being delimited by the body of the junction plate then returns to its initial shape once the fixing element has been erased, when the plate and the device are assembled in the junction position and each fixing element cooperates with the associated insert. In practice, and contrary to popular belief, resistance tests have shown that the fixing elements do not cause premature wear due to possible friction with the body of the junction plate.

According to one embodiment, each of the through orifices is coaxial with one of the fixing openings of one of the associated inserts of the junction plate. Preferably each of the through holes is also coaxial with the associated fixing hole of the reinforcement plate.

[0030] According to another aspect of the invention, it relates to a junction device for a conveyor belt intended to connect two end portions of at least one conveyor belt, the junction device being remarkable in that it comprises at least one junction plate as described above.

[0031] According to one embodiment, the junction device for a conveyor belt comprises a first junction plate according to one of the above embodiments and a second plate comprising a plurality of inserts, the two plates being configured to each cover a distinct side of the ends of the conveyor belt so that said conveyor belt is arranged between the two junction plates in the junction position, the first and second junction plates being fixed together by fixing means arranged to penetrate at least in part respectively a junction plate among the first and the second junction plate, one of the ends of the conveyor belt then the other junction plate among the first and the second junction plate.

According to one embodiment, a thickness of the first junction plate is greater than or equal to, preferably strictly greater than, a thickness of the second junction plate of the junction device, preferably greater than or equal to twice the the thickness of the second junction plate, preferably still greater than or equal to three times the thickness of the second junction plate. In technical jargon, such a configuration is referred to as a so-called “heavily coated” plate. In such a configuration, the strong cladding is carried on the upper junction plate of the junction device.

[0033] According to one embodiment, the fixing means comprise rod fixing means, preferably of the screw type, the fixing means each comprising, preferably, a head configured to cooperate with a part of the inserts and a section anchor, preferably provided with a thread, configured to cooperate with another part of said inserts. In alternative and/or complementary configurations, the fixing means may include rivets. [0034] According to one embodiment, the inserts configured to each cooperate with a head of the fixing means each comprise a washer pierced with the associated fixing opening bordered by a bowl capable of housing the head of the fixing means.

[0035] According to one embodiment, the inserts each configured to cooperate with an anchoring section of the fixing means each comprise a cylindrical tubular part delimiting the associated fixing opening, an interior cylindrical surface of which is capable of cooperating with a section anchoring the fixing means, the interior cylindrical surface preferably comprising a thread.

According to one embodiment, the first plate comprises only the threaded inserts configured to cooperate with the threaded anchoring sections of the fixing means. Alternatively, the first junction plate only comprises inserts configured to cooperate with the heads of the fixing means.

[0037] According to one embodiment, the through orifices are each coaxial with the fixing openings of each associated pair of inserts of the first plate and the second plate, in the junction position, when the first and second junction plates are in a joining position. Such a configuration allows vertical alignment of the inserts of each pair of inserts associated with a given fixing means to allow its anchoring.

[0038] According to one embodiment, a diameter of the through holes is strictly less than a diameter of the fixing opening of the associated insert, preferably strictly less than an external diameter of the head of the associated fixing element , preferably strictly less than a nominal diameter of the anchoring section of the associated fastening element, more preferably substantially equal to the diameter at the root of the thread of the anchoring section of the associated fastening element.

[0039] According to another aspect of the invention, it relates to a method of manufacturing a junction plate conforming to one of the embodiments described above, remarkable in that it comprises at minus the following steps: manufacturing a continuous succession of a plurality of junction plates in the form of a strip; and cuts, from said strip thus manufactured, junction plates following predetermined dimensions.

[0040] Such a manufacturing process is particularly advantageous in that it allows continuous manufacturing of several successive junction plates. Each of the first and second junction plates, intended to constitute the lower and upper junction plates of the junction device, are then cut from an associated strip or portion of strip thus manufactured and specifically adapted to the desired use.

[0041] According to another aspect, the invention also relates to a method of joining a first end portion and a second end portion of a conveyor belt by a joining device for a conveyor belt as described above comprising a first junction plate according to the invention and a second junction plate, characterized in that it comprises at least: a step of covering by the first junction plate and the second junction plate each of a distinct side of the end portions of the conveyor belt so that said conveyor belt is interposed vertically between the two junction plates, said first and second junction plates forming a first pair of wings which is adapted to pinch the first portion of the end of the conveyor belt and a second pair of wings which is adapted to pinch the second end portion of the conveyor belt; a step of inserting the second end of the conveyor belt between two wings of the second pair of wings, a step of fixing the second end portion of the conveyor belt with the two wings of the second pair of wings between which it is positioned, a step of inserting the first end of the conveyor belt between the two wings of the first pair of wings a step of fixing the first end of the conveyor belt with the two wings of the first pair of wings between which it is positioned.

BRIEF DESCRIPTION OF THE FIGURES

[0042] Other characteristics and advantages of the invention will emerge on reading the description which follows, with reference to the appended figures, which illustrate: Figure 1: a plan view of a conveyor belt joining device of the prior art, seen from above Figure 2: a longitudinal sectional view along section AA of Figure 1 of a junction device, representing in exploded view the different elements which constitute it. Figure 3a: a longitudinal sectional view of a conveyor belt junction device according to a first embodiment, representing in exploded view the different elements which constitute it. Figure 3b: a longitudinal sectional view of a junction device according to the same embodiment, in an intermediate assembly position. Figure 3c: a longitudinal sectional view of a junction device according to the same embodiment, in a junction position. Figure 4a: a longitudinal sectional view of a conveyor belt junction device according to another embodiment of the invention, representing in exploded view the different elements which constitute it. Figure 4b: a longitudinal sectional view of a junction device according to the same embodiment of the invention. [0043] For greater clarity, identical or similar elements are identified by identical reference signs in all of the figures.

[0044] In the description and the claims, to clarify the description and the claims, we will adopt, on a non-limiting basis, the terminology longitudinal, transverse and vertical with reference to the trihedron X, Y, Z indicated in the figures.

[0045] Furthermore, the terms “upper”, “lower” and their derivatives refer to the position or orientation of an element or component, this position or this orientation being considered when the junction plates are in service configuration and extend in a horizontal plane.

DETAILED DESCRIPTION OF EMBODIMENTS

[0046] Figure 1 is a plan view, from above, of a junction device 1 according to the prior art and shows an upper junction plate 4 of a junction device 1. We also note heads 5a screws 5 which constitute an example of means of assembling the junction devices.

[0047] The cutaways lia and 11b reveal two types of textile type reinforcements, which are woven: in the reinforcement lia the fabric is arranged in such a way that its weft threads, or its warp threads, are oriented at least approximately in the longitudinal direction of the joining device 1 while in the frame 11b the fabric is arranged so that its weft threads and its warp threads are oblique to the longitudinal direction of the joining device 1.

[0048] We recall that by convention the longitudinal direction X of the junction device 1 corresponds, in the present description, to the longitudinal direction which it connects. The transverse direction Y of the junction device 1 is, according to the same convention, the direction perpendicular to the longitudinal direction X. This convention is applied regardless of the effective dimensions of the junction device 1 in these two directions.

The junction device of Figure 1 is composed of three elements: an element forming an upper junction plate 4, an intermediate element 9 located under the middle part of the junction plate 4 which is not visible in Figure 1 other than by the two dotted lines located on either side of the two middle screws 5 delimiting the edges under the upper junction plate 4 ends of the conveyor belt 2 to be connected, and a lower junction plate element 4, not visible in Figure 1, which is located under the intermediate element 9 and under the upper junction plate element 4.

[0050] The exploded section in Figure 2 successively shows assembly screws 51 forming fixing means 5, the upper junction plate 4a, inserts 6 incorporated in the upper junction plate 4, the intermediate element 9 comprising an incorporated through-socket, arranged vertically along a vertical axis Z, the lower plate 3 comprising threaded inserts 7.

The inserts 6 arranged to receive the heads 5a of screws 51 are generally in the form of pierced washers 61 comprising a bowl capable of housing the heads 5a of the screws 5 intended to pass through the hole of the pierced washers. The central insert 6' is generally presented like the inserts 6 but it comprises a central tubular part, the interior cylindrical surface of which is capable of allowing passage, with very little play, to the corresponding screw 5, this screw does not therefore not screwing into the 6' insert. The central tubular part of the insert 6' protrudes from the lower surface of the upper junction plate 4.

The inserts 7 each comprise a central tubular part whose interior cylindrical surface is threaded and is capable of receiving a screw 51 screwed into the thread, said central tubular parts projecting from the upper surface of the lower junction plate 4 of the junction device 1. The middle inserts 7' of the lower plate appear as the inserts 7.

[0053] Figures 3a, 3b and 3c illustrate a junction device 1 according to a first embodiment of the invention. The junction device 1 comprises a first junction plate 4. In this embodiment, the junction device 1 also comprises a second junction plate 4'. These first and second junction plates 4, 4' each have a body 45 made of a flexible material and elastic, for example made of vulcanized rubber, or of a synthetic material such as polyurethane and they comprise a reinforcement plate 11 secured to the body 45 of the associated junction plates 4, 4'. The reinforcement plate 11 is made up of one or more layers of textile, so as to form a woven reinforcement. This material constitutes the body of each of these two junction plates 4, 4'. The reinforcement plate 11 comprises through fixing holes each surrounding at least the fixing means 5 in the junction position, or even a given insert.

The junction plates 4, 4' are configured to each cover a distinct side of end portions 21, 22 of a conveyor belt 2 so that the conveyor belt 2 is interposed vertically between the first and second plates of junction 4.4'. The first and second junction plates 4, 4' together form a first pair of wings 40 which grips the first end portion 21 of the conveyor belt 2 and a second pair of wings 42 which grips the second end portion 22 of the conveyor belt 2 in a joining position. The two junction plates 4, 4' are fixed together with the end portions 21, 22 of the conveyor belt 2 by fixing means 5 arranged to penetrate at least in part respectively the first upper junction plate 4, the portions ends 21, 22 then the second lower junction plate 4'.

The first junction plate 4 comprises a body 45 made of flexible and elastic material such as rubber. The first junction plate 4 has an exterior surface SI to be flush, that is to say level, with a useful surface of the conveyor belt 2 in the junction position. The exterior surface SI is here constituted by an exterior surface of the body. The useful surface area of the conveyor belt 2 corresponds to the surface area of the conveyor belt 2 on which the different materials or products conveyed rest. The first junction plate 4 also has an interior surface S2, opposite the exterior surface SI and constituted here by an interior surface of the body and of the reinforcement plate 11. The interior surface S2 is intended to cover a distinct side of the two portions ends 21,22 of the conveyor belt 2 in the junction position so as to extend astride these two end portions 21,22. The interior and exterior surfaces SI, S2 delimit a thickness E of the associated junction plate 4. [0056] The thickness E of the first junction plate 4 is greater than a thickness of the second junction plate 4', preferably greater than or equal to twice the thickness of the second junction plate 4', preferably even greater than or equal to three times the thickness of the second junction plate 4'. Such a junction plate 4 is described as a “heavy coating” plate. The reinforcement plate 11 of the junction plate 4 is housed inside the body 45 of the junction plate and extends parallel to the exterior surface SI. Here the thickness of the second lower junction plate 4' defined, and therefore measured, in a manner similar to that of the first upper junction plate 4, between its exterior and interior surfaces in a zone without insert, the exterior surface being this time flush with an interior surface of the conveyor belt 2 in the junction position intended to come into contact with the return and drive members of said conveyor belt 2 opposite the useful surface of said conveyor belt 2.

The first junction plate 4 forming the upper junction plate of the junction device, further comprises a plurality of inserts 6 for receiving at least part of the fixing means 5 of the junction device 1, with at least the end portions 21, 22. These inserts 6 are embedded at least partly in the body 45 and each having a fixing opening associated with one of the fixing holes of the reinforcement plate 11 so as to surround a rim of the associated fixing hole on one side of the reinforcement plate 11, to receive means 5 of the junction device 1, with at least the end portions 21, 22.

The frame 11 and the inserts 6 are housed in a lower half of the junction plate 4 with respect to its thickness E adjoining the interior surface S2, preferably by a vulcanization process. By the term "lower half", we designate a part of the junction plate 4 which extends from the interior surface S2 to a median limit equidistant from the interior and exterior surfaces SI, S2, this median limit forming a plane of junction P of the junction plate 4. The lower half is opposite the “upper half” of the junction plate 4 with respect to this median plane P, which upper half is superimposed on the lower half. The upper half of the junction plate 4 is thus constituted by the sole material constitutive of its body 45 and is strictly devoid of inserts or fixing elements 5, which gives the first junction plate 4 increased flexibility and better dynamic behavior, in particular in contact with drive members and of referrals. This upper part is also the one which undergoes the most elastic deformation when a portion of conveyor belt passes at the level of a return member, offering both significant extensibility in the longitudinal direction of the conveyor belt and resistance adapted to wear, since a thickness of the material of the body 45 located above the reinforcement plate 11 and the inserts 6 is relatively large due to the fact that it is a heavily coated plate. In particular, the body 45 has a minimum thickness measured between the exterior surface SI and the inserts 6, greater than or equal to a distance equal to a height of the associated inserts 6. This ensures a good compromise between elasticity and resistance.

[0059] In the embodiment described with reference to Figures 3a, 3b and 3c, the body 45 comprises through orifices 47 extending to the right of each of the inserts 6 from the interior surface SI of the body at which they open towards the interior surface S2 of the body 45. These through orifices 47 of the junction plate 4 have a cylindrical shape and are erected generally vertically. The through holes 47 are configured to be crossed in their length by the fixing means 5 of the junction plate 4. The body 45 has an extensibility of between 15% and 40%, preferably between 20% and 30%, so that the through orifices 47 deform elastically when they are crossed by the fixing elements 5. Here, each through orifice 47 is oriented so as to be coaxial with a fixing opening of an associated insert 6 of the first junction plate 4 and an associated fixing hole of the reinforcement plate 11. Each through orifice 47 extends continuously to the fixing opening of the associated insert 6 itself surrounding an associated fixing hole of the reinforcement plate 11. In such a configuration, the through orifices 47 delimited by the body 45 each provide a function of feed corridor from the fixing means 5 to the associated insert 6 of the junction plate 4 with which it can cooperate. Like the first junction plate 4, the associated second junction plate 4' comprises a plurality of inserts 7, preferably vulcanized.

The fixing means 5 of the junction device 1 each comprise a head 5a configured to cooperate with part of the inserts 6, 7 and an anchoring section 5b to cooperate with the other part of the inserts 6,7.

[0062] Generally speaking, each junction plate 4, 4' of the junction device 1 comprises first interfaces for cooperating with the heads 5a of the fixing means 5 and second interfaces for cooperating with the anchoring sections 5b of the means fixing device 5, the second interfaces being distinct from the first interfaces and comprising inserts incorporated at least partly in the associated junction plate 4, 4'. In the embodiment described, the anchoring section 5b is provided with a thread.

[0063] Each fixing means 5 thus locally ensures fixing of one of the junction plates among the first and second junction plates 4, 4' with the other junction plate among the first and second junction plates 4, 4', while passing through one of the end portions 21, 22 of the conveyor belt 2 interposed between the first and second junction plates 4, 4' in the junction position. Thanks to a pair of a first type of inserts among the inserts 6, 7 and a second type of associated inserts among the inserts 6, 7 of a given fixing means 5, it is possible to maintain the locked fixing .

[0064] In this embodiment, the inserts 6 of the first junction plate 4 form a first part of the inserts, of the first interface. They include a pierced washer 61 comprising a bowl 62 capable of housing the head 5a of the fixing means 5. When joining the first and second end portions of the conveyor belt 2 together, each screw 5 is inserted through the one of the corresponding orifices 47 of the first junction plate 4 until its head 5a is housed in the bowl 62 of the washer 61 forming the insert 6. This type of insert is integrally embedded in the body 45 of the junction plate. The inserts 7 of the second junction plate 4' form a second part of the inserts, of the second interface. They comprise a cylindrical tubular part 73, an interior cylindrical surface 74 of which is capable of cooperating with the anchoring section 5b of the fixing means 5. In the embodiment described, the interior cylindrical surface 74 comprises a thread. When joining the first and second end portions of the conveyor belt 2 together, each screw 5 is inserted through one of the corresponding orifices 47 of the first junction plate 4 until its head 5a comes into place. housed in the bowl 62 of the washer 61 forming the insert 6 and, concomitantly, that the threaded anchoring section 5b passes through the corresponding end portion of the conveyor belt 2 then screws into the thread 74 of the insert 7. This type of insert is partly embedded in the body 45 of the junction plate, at least a portion of the cylindrical tubular part 73 being projecting relative to the interior surface of the associated junction plate.

[0066] In the junction device 1, the through orifices 47 of the junction plate 4 are each coaxial with each associated pair of inserts 6,7 of the first junction plate 4 and the second junction plate 4'. In the embodiment described, a diameter of the through orifices 47 is strictly less than an external diameter of the head 5a of the associated fixing element and here strictly less than a diameter of a fixing opening of the associated insert 6 so that the body 45 partly covers the fixing openings of the inserts while ensuring the passage of the rod of the associated fixing element 5. In particular here, the diameter of the through orifices 47 is equal to the diameter at the root of the thread of the anchoring section 5b of the associated fixing element 5. In this way, the screw can be inserted into the insert 6 after passing through the through hole 47, screwing into the material of the body 45 which partly covers the fixing openings of the inserts 6. In other words , this allows screwing of the fixing element 5 into the body 45 delimiting the associated orifice 47. Thus, the through holes 47 deform elastically when the fixing element 5 is introduced, then return to their initial diameter, at least at the level of the screw head, and have a function of ensuring the passage of the screw by screwing. This also makes it possible to maintain prepositioned screws in the body of the junction plate 4. The exterior surface SI therefore presents a useful surface area greater than that of the prior art where the screw heads come level with this surface of the conveyor belt. In addition, the size of the orifices 47 reduces the risk of cracks appearing, which increases the lifespan of the associated junction plate 4. In practice we also see that the passage of the screw does not create premature wear of the junction plate.

[0067] This embodiment allows mounting of the junction device 1 from above on a conveyor with as few cavities and roughness as possible to thus limit degradation due to abrasion. The joint coating can wear in the same way as the conveyor belt without affecting the fasteners and inserts. With shorter screws, better dynamic operation is ensured on heavily coated belts.

[0068] Figures 4a and 4b illustrate a junction device 1 according to another embodiment of the invention described which differs from the previous one essentially in that the inserts 6 of the first junction plate 4, upper, form part of the inserts, here of the second interface, and in that the body 45 of the first upper junction plate covers completely, and not only in part, the openings for fixing the inserts 6. They include a cylindrical tubular part 63 delimiting the opening fixing and of which an interior cylindrical surface 64 is capable of cooperating with the anchoring section 5b of the fixing means. The inserts 7 of the second, lower junction plate 4' form part of the inserts, here of the first interface. They include a pierced washer 71 comprising a cup 72 delimiting the fixing opening and capable of housing the head 5a of the fixing means 5. In the embodiment described, the interior cylindrical surface 74 includes a thread.

[0069] Here, the orifices 47 are not through and extend from the interior surface S2 of the body 45 in the lower half of the first junction plate 4. In other words, the body 45 which completely covers the openings for fixing the inserts 6. The exterior surface SI is thus free of any interface which would represent areas conducive to the appearance of structural defects such as cracks. [0070] This embodiment allows the junction device to be mounted from below on a conveyor but allows the junction to be covered without a hole on the face in contact with the materials to be transported. This offers an advantage since the coating will be as smooth as the belt coating, and therefore less susceptible to abrasion. The coating thickness may vary depending on the coating thickness of the belt. In this case, the screw length is no longer influenced by the coating thickness. Shorter screws ensure better dynamic operation.

[0071] Naturally, the invention is described in the above by way of example. It is understood that those skilled in the art are able to carry out different variants of the invention without departing from the scope of the invention.

[0072] It is emphasized that all the characteristics, as they emerge for a person skilled in the art from the present description, the drawings and the attached claims, even if concretely they have only been described in relation to other specified features, both individually and in any combinations, may be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or technical circumstances make such combinations impossible or meaningless.

Claims

CLAIMS Junction plate (4) for a junction device (1) of a conveyor belt (2) intended to connect two end portions (21, 22) of at least one conveyor belt (2), the junction plate ( 4) having an exterior surface (SI) to be flush with a useful surface of the conveyor belt (2) in the junction position and an interior surface (S2) opposite the exterior surface (SI), and intended to cover at least partially the two end portions (21, 22) of the conveyor belt (2) in the junction position, the junction plate comprising: a body (45) of flexible material, having an exterior surface forming the exterior surface (SI) of the junction plate (4); a reinforcement plate (11) having through fixing holes, secured to the body; and a plurality of inserts (6) embedded at least partly in the body (45) and each having a fixing opening associated with one of the fixing holes so as to surround a rim of the associated fixing hole with a side of the reinforcing plate (11), to receive fixing means (5) of the junction device (1) with the end portions (21, 22); the junction plate (4) being characterized in that the body (45) covers at least partly the fixing openings of the inserts. Junction plate (4) according to the preceding claim, characterized in that the body (45) has a minimum thickness measured between the exterior surface (SI) and the inserts (6), greater than or equal to a distance equal to a height associated inserts. Junction plate (4) according to claim 1 or 2, characterized in that the junction plate (4) has an exterior surface (SI) constituted by an exterior surface of the body (45) and an interior surface (S2) opposite to there exterior surface (SI) and constituted by an interior surface of the body (45) and/or of the reinforcement plate (11), the exterior surface (SI) and the interior surface (S2) being equidistant from one of the another on either side of a median plane (P) of the junction plate (4), the reinforcement (11) and the inserts (6) being positioned on the interior side of the junction plate relative to the plane median (P), preferably between the median plane and the interior surface (S2).

4. Junction plate (4) according to any one of the preceding claims, characterized in that the reinforcement plate (11) is housed in the body (45) and extends at a constant distance from the exterior surface (SI ).

5. Junction plate (4) according to any one of the preceding claims, characterized in that the body (45) is formed from an elastomeric material, preferably rubber, and has an extensibility of between 15% and 40%, preferably between 20% and 30%.

6. Junction plate (4) according to any one of the preceding claims, characterized in that the body (45) of the junction plate (4) comprises orifices (47) extending from the interior surface (S2) of the body (45) in the lower half of the junction plate (4), the orifices (47) being configured to partially accommodate the fixing means (5).

7. Junction plate (4) according to any one of the preceding claims, characterized in that the body (45) comprises through orifices (47), extending from the exterior surface (SI) of the body (45) of the junction plate (4) towards the interior surface (S2), the orifices (47) being configured to each be crossed by one of the fixing means (5).

8. Junction plate (4) according to the preceding claim, characterized in that each of the through orifices (47) is coaxial with one of the fixing openings of one of the inserts (6) associated with the junction plate (4) .

9. Junction device (1) for conveyor belt (2) intended to connect two end portions (21, 22) of at least one conveyor belt (2), characterized in that it comprises at least one junction plate (4) according to any one of the preceding claims. Junction device (1) for conveyor belt (2) according to the preceding claim, characterized in that it comprises a first junction plate (4) according to one of claims 1 to 8 and a second plate (4') comprising a plurality of inserts (7), the two plates (4, 4') being configured to each cover a distinct side of the ends of the conveyor belt (2) so that said conveyor belt (2) is arranged between the two junction plates in the junction position, the first and second junction plates (4, 4') being fixed together by fixing means (5) arranged to penetrate at least partly respectively one junction plate among the first and the second junction plate (4, 4'), one of the end portions (21, 22) of the conveyor belt (2) then the other junction plate among the first and second junction plates (4, 4' ). Junction device (1) according to the preceding claim, characterized in that a thickness (E) of the first junction plate (4) is greater than or equal, preferably strictly greater, to a thickness of the second junction plate (4 ') of the junction device (1), preferably greater than or equal to twice the thickness of the second junction plate (4'), more preferably greater than or equal to three times the thickness of the second junction plate (4'). Junction device (1) for conveyor belt (2) according to the preceding claim, characterized in that the fixing means (5) comprise rod fixing means, preferably of the screw type, the fixing means each preferably comprising a head (5a) configured to cooperate with a part of the inserts (6, 7) and an anchoring section (5b), preferably provided with a thread, configured to cooperate with another part of the inserts (6, 7). Junction device (1) for conveyor belt (2) according to the preceding claim, characterized in that the inserts (6, 7) configured to cooperate with a head (5a) of the fixing means (5) each comprise a washer (61 , 71) breakthrough of the associated fixing opening bordered by a bowl (62, 72) capable of housing the head (5a) of the fixing means (5) and the inserts (6, 7) configured to cooperate with an anchoring section (5b) of the fixing means (5) each comprise a cylindrical tubular part (63 , 73) delimiting the associated fixing opening, an interior cylindrical surface (64, 74) of which is capable of cooperating with the anchoring section (5b) of the fixing means (5), the interior cylindrical surface (64, 74) preferably comprising a tapping.

14. Junction device (1) according to the preceding claim, characterized in that the first junction plate (4) comprises only threaded inserts (6) configured to cooperate with the threaded anchoring sections (5b) of the fixing means (5).

15. Junction device (1) according to claim 13, characterized in that the first junction plate (4) comprises only inserts (6) configured to cooperate with the heads (5a) of the fixing means (5).

16. Junction device (1) according to any one of claims 10 to 15, the first junction plate (4) being in accordance with claim 7 or 8, characterized in that the through orifices (47) are each coaxial with the openings for fixing each pair of inserts (6,7) associated with the first junction plate (4) and the second junction plate (4'), in the junction position.

17. Junction device (1) according to any one of claims 10 to 13 and 15, including claim 13, the first junction plate (4) being in accordance with claim 7 or 8, characterized in that a diameter of the through orifices (47) is strictly less than a diameter of the fixing opening of the associated insert (6), preferably strictly less than an external diameter of the head (5a) of the fixing element (5) associated, preferably strictly less than a nominal diameter of the anchoring section (5b) of the associated fixing element (5), more preferably substantially equal to the diameter at the root of the thread of the anchoring section (5b) of the associated fixing element (5). Method of manufacturing a junction plate (4) according to any one of claims 1 to 8, characterized in that it comprises at least the following steps: manufacturing a continuous succession of a plurality of plates of junction (4) in strip form; and cuts, from said strip thus manufactured, junction plates (4) following predetermined dimensions. Method for joining a first end portion and a second end portion of a conveyor belt (2) by a joining device (1) for a conveyor belt (2) according to any one of claims 9 to 18 comprising a first junction plate (4) according to any one of claims 1 to 8 and a second junction plate (4'), characterized in that it comprises at least: a step of covering by the first plate junction (4) and the second junction plate (4') each on a separate side of the end portions (21, 22) of the conveyor belt (2) so that said conveyor belt is interposed vertically between the two junction plates (4, 4'), said first and second junction plates (4, 4') forming a first pair of wings (40) which is adapted to grip the first end portion (21) of the strip conveyor (2) and a second pair of wings (42) which is adapted to grip the second end portion (22) of the conveyor belt (2)

> a step of inserting the second end of the conveyor belt (2) between two wings of the second pair of wings (42), a step of fixing the second portion (22) of the end of the conveyor belt ( 2) with the two wings of the second pair of wings (42) between which it is positioned, a step of inserting the first end portion (21) of the conveyor belt (2) between the two wings of the first pair of wings (40) a step of fixing the first end portion (21) of the conveyor belt (2) with the two wings of the first pair of wings (40) between which it is positioned.