Tyre building drum provided with an integrated attachment device comprising a retractable clamping blade

Abstract

The invention relates to a drum (1) for building a tyre, the drum (1) having a central axis (Z1) and having a receiving surface (2) intended to receive at least one constituent element of the tyre (3), the drum comprising an attachment device (5) which is intended to hold the constituent element of the tyre (3) on the receiving surface (2), the attachment device (5) comprising a base (6) through which the attachment device is attached to the drum, a clamping jaw (7) formed by a leaf spring (40), and an actuating mechanism (10) with a four-bar linkage (20), comprising a first arm (26) and a second arm (27) that is shorter than the first arm (26), for passing the clamping jaw (7) alternately from a rest position (P0) to a working position (P1) in which the clamping jaw (7) exerts a clamping force (F_clamp) on the constituent element of the tyre (3).

Description

BANDAGE MANUFACTURING DRUM PROVIDED WITH AN ON-BOARD FIXING DEVICE COMPRISING A RETRACTABLE CLAMPING BLADE

[0001] The present invention relates to the field of manufacturing tires, in particular pneumatic tires for vehicle wheels.

[0002] The present invention relates more particularly to drums which are used for manufacturing an annular bandage component by winding onto said drum one or more elements which are in the form of a strip.

[0003] The present invention is particularly applicable when it is desired to manufacture annular reinforcements, called "frets", intended to form a strapping belt in the crown of a vehicle wheel tire, and for this purpose a rubber-based strip is wound onto a drum, in several contiguous helical turns (which may for example overlap axially or on the contrary be juxtaposed axially without overlapping), which contains continuous and mutually parallel reinforcing threads, arranged in the length direction of said strip.

[0004] One of the difficulties of such a winding operation is to hold firmly on the drum, in the desired starting position, the front end portion of the strip, to allow the drum, when said drum is rotated, to drive said strip behind it without causing the front end portion of said strip to slip or fall under the effect of tension, gravity, or centrifugal force.

[0005] When the rubber constituting the belt has sufficient tack, i.e. sufficient intrinsic adhesive power, it is possible to consider fixing the front end portion of the belt to the drum simply by placing said end portion against the surface of said drum. The strength of such fixing obviously depends on the affinity that exists between, on the one hand, the rubber-based material of the belt and, on the other hand, the surface of the drum. This affinity can vary greatly depending on whether the surface of the drum on which it is desired to place the component of the bandage is metallic and bare, or, on the contrary, already coated with a first component of the bandage forming a first rubber-based layer.

[0006] Similarly, when the tape contains magnetically sensitive metal reinforcement wires, a magnet can be used to adhere the tape to the drum.

[0007] However, not all tapes are sticky or magnetic.

[0008] It was therefore envisaged, as presented in application WO-2020 / 08069 filed by the Applicant, a fixing device which uses retractable needles which deploy from the drum, to project from the surface of the drum, obliquely to said surface of the drum, in order to stitch the strip and thus hold said strip in place.

[0009] While such a device can certainly produce good results, it can also sometimes suffer from certain drawbacks.

[0010] A first possible drawback is the relative fragility of the needles.

[0011] A second possible disadvantage is the difficulty of adapting the device to the variety of bandages manufactured, since, depending on the bandage manufactured, and in particular depending on the dimensions of said bandage, it may be necessary to lay strips of very different widths, and / or to adopt starting winding positions which vary greatly along the axis of the drum, from one bandage model to another or from one constituent element to another.

[0012] The objects assigned to the invention therefore aim to remedy the aforementioned drawbacks and to propose a new fixing device making it possible to temporarily and reversibly hold a constituent element of a bandage on a manufacturing support such as a drum, a fixing device which, while guaranteeing firm and reliable holding of the constituent element of the bandage, and while remaining light, compact and inexpensive, has good versatility allowing it to adapt to a wide variety of bandages and associated manufacturing configurations.

[0013] The objects assigned to the invention are achieved by means of a drum for manufacturing a bandage, said drum having a central axis and presenting a radially external surface, called a "receiving surface", which extends along and around said central axis and which is intended to receive at least one constituent element of said bandage, said drum comprising a fixing device which is intended to hold said constituent element of the bandage on said receiving surface, said drum being characterized in that that the fixing device comprises: - a base which is fixed to the drum, so that the fixing device is carried by said drum, - a clamping jaw which is arranged to adopt a position called the “working position”, in which said clamping jaw bears on a radially external face of the constituent element of the bandage while an opposite face, forming a radially internal face, of said constituent element of the bandage rests on the receiving surface, in order to exert on said constituent element of the bandage a radial compression force, called the “clamping force”, which holds said constituent element of the bandage on said receiving surface; - an actuating mechanism, which is carried by the base and which connects the clamping jaw to said base, said actuating mechanism being arranged to cause the clamping jaw to execute, relative to the base and therefore relative to the receiving surface, alternately a first movement, called an “engagement movement”, which makes it possible to bring the clamping jaw from a rest position to the working position, and a second movement, called a “disengagement movement”, which makes it possible to return the clamping jaw to the rest position by moving the clamping jaw back from the working position both along a radial component, in order to release the clamping force, and along an axial component, in order to free the axial range which is occupied, on the receiving surface, by the constituent element of the bandage.

[0014] Advantageously, by integrating the fixing device into the drum, so that said fixing device is permanently secured to the drum and more particularly secured to the receiving surface of said drum, a simple, compact and lightweight structure is obtained, which does not require, in particular, the provision of complex equipment, which would be separate from the drum, to carry and position the fixing device opposite the receiving surface and / or to drive the fixing device in rotation synchronously with the drum.

[0015] Advantageously, the actuating mechanism according to the invention makes it possible to easily clamp the constituent element of the bandage by pinching using a clamping jaw which, during the engagement movement, approaches the receiving surface by an approach trajectory comprising a radial component, and which can thus press effectively and stably the constituent element of the bandage against the receiving surface of the drum, by applying a clamping force which is radial, and which is therefore oriented substantially in a direction normal to said receiving surface.

[0016] The clamping jaw can thus come into contact with the constituent element of the bandage, then intensify the force that it exerts on said constituent element of the bandage, against the receiving surface which supports said constituent element of the bandage, until the desired intensity of the radial clamping force is reached, without risk of sliding the constituent element of the bandage on the receiving surface, relative to the position that it is desired to assign to said constituent element of the bandage and which typically corresponds to the starting position of the winding. The fixing device according to the invention thus makes it possible to reliably and reproducibly achieve, from one constituent element of the bandage to another, a tightening and a holding that is both firm and stable.

[0017] Furthermore, this same actuating mechanism according to the invention makes it possible to precisely define the position and extent of the area which is covered, in particular axially, by the clamping jaw when said clamping jaw is in the working position. This ensures in particular that the area covered by the clamping jaw in the working position is sufficiently extensive to firmly hold the constituent element of the bandage on the receiving surface, while being sufficiently restricted so that the clamping jaw does not interfere, during the winding of said constituent element of the bandage onto the drum, with the laying trajectory which is followed by said constituent element of the bandage, typically here a helical laying trajectory.

[0018] In other words, the fixing device, and more particularly the clamping jaw, is advantageously configured so as not to hinder the installation of the constituent element of the bandage, and in particular so as not to become stuck under one or more thicknesses of said constituent element of the bandage thus installed.

[0019] Finally, the actuating mechanism according to the invention advantageously makes it possible, during the release movement, once the constituent element of the bandage is wound on the drum, to first move the clamping jaw away from the receiving surface at least according to a movement component which is radial centrifugal, and consequently substantially normal to the receiving surface, which makes it possible to eliminate the clamping by releasing the radial clamping force and to separate the clamping jaw from the constituent element of the bandage while avoiding damage or accidental sliding of the bandage component on the receiving surface.

[0020] This same actuating mechanism also makes it possible, still in the release movement, to axially retract the clamping jaw, advantageously without said clamping jaw rubbing against the constituent element of the bandage, and this in such a way as to place said clamping jaw in a rest position which is located outside the area of ​​the receiving surface which is axially occupied by the constituent element of the bandage located on the drum.

[0021] The area of ​​the receiving surface thus cleared, and therefore the component element of the bandage located on the drum, can then be easily accessed, either to place and wind over said component element of the bandage a second component element of the bandage, in order to continue the current manufacturing cycle with a view to producing a laminated bandage structure, or to remove the annular block formed by said component element of the bandage located on the drum, and thus free the receiving surface of the drum so that, without being hindered by the clamping jaw, the component element of a following bandage can be engaged and thus a new manufacturing cycle can be started.

[0022] Thus, the fixing device according to the invention does not hinder the initial installation and attachment of the constituent element of the bandage on the drum, nor the winding of said constituent element of the bandage onto the drum, nor the removal, after winding, of said constituent element of the bandage.

[0023] Furthermore, as will be detailed later, the fixing device according to the invention is easily reconfigurable, and in particular makes it possible to adapt the axial extent of said clamping jaw and / or to adapt the axial and / or radial travel of the clamping jaw, by a simple change of clamping jaw, depending on the dimensions of the constituent element of the bandage, the desired starting position, and where appropriate the degree of overlap that it is desired to obtain between consecutive turns of said constituent element of the bandage. The fixing device thus has a great capacity to adapt to very varied structures and dimensions of bandages.

[0024] Other objects, characteristics and advantages of the invention will appear in more detail on reading the description which follows, as well as with the aid of the appended drawings, provided for purely illustrative and non-limiting purposes, among which:

[0025] Figure 1A illustrates, in an overall perspective view, a drum according to the invention which is provided with a fixing device integrated into one of the tiles constituting said drum, a fixing device whose clamping jaw is in the working position and holds the front end portion of a strip pressed against the receiving surface of said drum, a receiving surface which here corresponds to the radially external face of the tile.

[0026] Figure 1B is an inset detail view of Figure 1, in the area of ​​the drum which carries the fixing device.

[0027] Figure 2 is a detailed perspective view of the drum tile of Figures 1 A and 1 B, the fixing device of which exerts a substantially radial clamping force on the end portion of the strip by means of its clamping jaw placed in the working position.

[0028] Figure 3 is a detailed view, with material broken away, of the tile of Figure 2 showing the actuating mechanism of the fixing device, here an actuating mechanism which comprises an articulated quadrilateral carrying the clamping jaw, with the clamping jaw in the working position.

[0029] Figure 4 is a detailed view, with material broken away, of the tile of Figures 2 and 3 showing the actuating mechanism of the fixing device, the clamping jaw this time being in the rest position.

[0030] Figures 5, 6, 7 and 8 illustrate, according to detailed sectional views in a radial plane containing the central axis of the drum, the fixing device and its actuating mechanism in different successive phases of the release movement, Figure 5 corresponding to the working position, Figure 8 to the rest position, and Figures 6 and 7 to a first intermediate position and a second intermediate position.

[0031] The present invention relates to a drum 1 for manufacturing a bandage.

[0032] The bandage may preferably be a bandage intended to equip a vehicle wheel, and more particularly a pneumatic bandage. However, in a non- limiting, the invention can also be used to manufacture bandages of other types, such as for example tracks, belts or even conveyor belts.

[0033] As is clearly visible in Figure 1A, the drum 1 has a central axis ZI and has a radially external surface 2, called the “receiving surface” 2, which extends along and around said central axis ZI and which is intended to receive at least one element 3 constituting said bandage.

[0034] The receiving surface 2 has a substantially circular shape around the central axis Zl, preferably a straight cylindrical shape (whose generatrices are straight lines parallel to the central axis Zl), or, even more preferably, a slightly curved, barrel-shaped shape (whose generatrices are curved and concave relative to the central axis Zl, in order to be curved outwards).

[0035] By "axial" we mean a direction which is parallel to the axis considered, here more particularly a direction parallel to the central axis Zl of the drum.

[0036] By "radial" is meant a direction which is perpendicular to the axis considered, here more particularly a direction Y1 which is perpendicular to the central axis Zl of the drum or, if applicable, by equivalence, a direction which is normal to the receiving surface 2 at the point considered.

[0037] By "circumferential" is meant a direction which is orthoradial, that is to say a direction which, at a point considered, is normal to the radial plane which contains the axis considered and which passes through said point considered. More particularly, we will consider here a circumferential direction XI which is normal, at the point considered, to the radial plane which contains the central axis Zl of the drum 1 and which passes through the point considered. The circumferential direction is therefore contained in a plane normal to the axis considered, and, in this plane normal to the axis considered, is perpendicular to the radius which joins said axis considered to the point considered.

[0038] The constituent element of the bandage 3 is preferably a strip 4, which, when said constituent element of the bandage 3 reaches the receiving surface 2, extends in length substantially in a circumferential direction XI tangent to the receiving surface 2, in width W3 substantially in the axial direction defined by the central axis Zl of the drum, and in thickness E3 in the radial direction Yl.

[0039] The constituent element of the bandage 3, and more particularly said strip 4, preferably contains reinforcing threads which extend continuously in the direction of the length of said constituent element of the bandage 3, parallel to each other and parallel to the lateral edges of said constituent element of the bandage 3. These reinforcing threads have the function of making the constituent element of the bandage 3 almost inextensible in longitudinal traction.

[0040] These reinforcing threads can be made of any suitable material, for example metallic, or polymer (for example aramid), natural textile fibers, or even glass fibers.

[0041] These reinforcing threads can be integrated into a matrix made of any suitable material.

[0042] In particular, the metal reinforcing wires or the polymer reinforcing wires may preferably be embedded in a rubber-based matrix. Alternatively, fiberglass reinforcing wires may be embedded in a resin matrix, such that the constituent element of the bandage 3 forms a glass-resin composite.

[0043] Preferably, the drum 1 is mounted to rotate around its axis Zl, so that the rotation of said drum 1, and therefore of its receiving surface 2, makes it possible to wind the constituent element of the bandage 3 onto the receiving surface 2, in one or more turns around the central axis Zl, in such a way that an annular block is formed with said constituent element of the bandage 3.

[0044] The drum 1 comprises a fixing device 5 which is intended to hold the constituent element of the bandage 3 on the receiving surface 2.

[0045] The fixing device 5 is intended to ensure temporary and reversible fixing of the constituent element of the bandage 3 on the receiving surface 2, in particular at the start of the winding operation, and more preferably throughout the duration of the winding operation. Once the winding operation is complete, the fixing device 5 is designed to be able to release the constituent element of the bandage 3, and more generally the annular block which will result from the winding operation.

[0046] As can be seen in particular in figures 1A, 1B and 2, the fixing device 5 is more particularly intended to hold a front end portion 3F of the constituent element of the bandage 3 in an area of ​​the receiving surface 2 which corresponds to the starting position from which it is desired to wind the constituent element of the bandage 3 onto the drum 1.

[0047] In practice, the aforementioned front end portion 3F advantageously corresponds to the front end of the strip 4.

[0048] According to the invention, the fixing device 5 comprises a base 6 which is fixed to the drum 1, so that the fixing device 5 is carried by said drum 1.

[0049] Advantageously, the fixing device 5 is thus mounted on the drum 1, and permanently coupled to the receiving surface 2, as long as the base 6 remains fixed on the drum 1. The fixing device 5 is therefore spontaneously integral with the movements of the drum 1, and more particularly with the movements of the receiving surface 2, here with the rotational movements of the receiving surface 2 around the central axis Zl.

[0050] In this way, said fixing device 5 does not require additional equipment separate from the drum 1 to bring said fixing device 5 closer to the drum 1, properly position the fixing device 5 relative to the drum, then drive said fixing device 5 in synchronous rotation with the drum 1 around the central axis Zl.

[0051] The attachment of the base 6 to the drum is advantageously reversible, so as to allow the disassembly of the attachment device 5 for maintenance or replacement.

[0052] This fixing can be achieved, for example, using screws.

[0053] The base 6 in particular allows the fixing device 5 to remain fixed on the drum 1, and therefore coupled to the receiving surface 2, without interruption from one operation of winding a constituent element of a bandage 3 to another operation of winding a constituent element of a bandage 3.

[0054] Thus, the base 6 allows in particular the fixing device 5 to remain fixed on the same drum 1 while, if necessary, said drum 1 is transferred between several successive manufacturing stations, which allow successively placing on said drum 1, and in particular stacking in successive layers on said drum 1, several elements 3 constituting the same bandage. The base 6 also allows the fixing device 5 to remain fixed on the same drum 1 without interruption during several manufacturing cycles. consecutive cycles during which said same drum 1 is reused in each manufacturing cycle in order to manufacture several separate successive bandages on said drum 1.

[0055] The fixing device 5 also comprises a clamping jaw 7 which is arranged to adopt a position PI called the “working position” PI, in which, as can be seen in FIGS. 1A, 1B, 2 and 5, said clamping jaw 7 bears on a radially external face 3_out of the element 3 constituting the bandage while an opposite face, forming a radially internal face 3_in, of said element 3 constituting the bandage rests on the receiving surface 2, in order to exert on said element 3 constituting the bandage a radial compression force F clamp, called the “clamping force” F clamp, which holds said element 3 constituting the bandage on said receiving surface 2.

[0056] In the working position PI, the clamping jaw 7 thus ensures stable holding of the constituent element of the bandage 3 by pinching against the receiving surface 2. This makes it possible to begin the winding operation, and more particularly allows the receiving surface 2 to rotate around the central axis ZI and to drive in its wake, by circumferential traction, the constituent element of the bandage 3, without risk of said constituent element of the bandage 3 moving on the receiving surface 2 relative to its desired starting position or accidentally detaching from the receiving surface 2.

[0057] Preferably, for better stability, the constituent element of the bandage 3 is compressed by the clamping force F clamp in the direction of its thickness E3, thickness E3 which here corresponds to the distance separating the radially internal face 3_in from the radially external face 3_out of said element 3, and which also preferably corresponds to the smallest dimension of said constituent element of the bandage 3.

[0058] It will be noted that the front end portion 3F of the constituent element of the bandage 3, here more particularly of the band 4, may have a straight front, that is to say a front which extends perpendicularly to the two edges of the element 3, here of the band 4, or else a beveled front which extends obliquely from one edge to the other, thus forming an angle, and therefore a point, relative to one of the edges of the element 3, here one of the edges of the band 4.

[0059] However, the fixing device 5 according to the invention is particularly well suited to holding strips 4 having a front bevel, because said fixing device 5 is capable of ensuring a good grip on the strip 4, even if the radially external face 3_out of said strip 4 has a restricted surface area due to the presence of said bevel.

[0060] The fixing device 5 further comprises an actuating mechanism 10, which is carried by the base 6 and which connects the clamping jaw 7 to said base 6, said actuating mechanism 10 being arranged to cause the clamping jaw 7 to execute, relative to the base 6 and therefore relative to the receiving surface 2, alternately: - a first FWD movement, called the “engagement movement” FWD, which allows the clamping jaw 7 to be brought from a rest position PO to the working position PI, - and a second movement BWD, called “release movement” BWD, which makes it possible to return the clamping jaw 7 to the rest position PO by moving the clamping jaw 7 back from the working position PI both according to a radial component BWD R1, here a centrifugal radial component, in order to release the clamping force F clamp, and according to an axial component BWD A, in order to free the axial area 11 which is occupied, on the receiving surface 2, by the constituent element of the bandage 3.

[0061] The clamping jaw 7 is therefore a movable jaw placed under the control of the actuating mechanism 10.

[0062] Advantageously, when the clamping jaw 7 occupies its rest position PO, as illustrated in FIGS. 4 and 8, said clamping jaw 7 is retracted to a sufficient axial distance so as not to hinder the installation of a following constituent element 3.

[0063] Thus, for example, if a first winding operation has made it possible to wind a strip 4 onto the drum in several turns to form a reinforcement belt, the release movement BWD makes it possible to completely free the space located radially above said strip 4, and more generally radially above said reinforcement belt, which frees up access for the installation of another constituent element 3, such as a tread, which is superimposed on said reinforcement belt.

[0064] Preferably, the trajectory T7 of the clamping jaw 7 during the release movement BWD is curved, so as to combine with an axial component BWD A firstly a first radial component BWD R1 (figure 6) according to which the clamping jaw clamping 7 moves away from the central axis ZI of the drum, in order to detach from the constituent element of the bandage 3, without rubbing on the radially external face 3_out of said element 3, then a second radial component BWD R2 according to which the clamping jaw approaches the central axis ZI in order to reach the rest position PO (figure 8).

[0065] Thus, the trajectory T7 of the clamping jaw 7 during the release movement B WD has, in a radial reference plane containing the central axis ZI of the drum 1, a concave, quasi-parabolic shape, relative to the central axis ZI of the drum.

[0066] Advantageously, such a concave trajectory T7 makes it possible to reach a rest position PO in which the clamping jaw 7 projects little or not at all radially relative to the receiving surface 2.

[0067] More particularly, when the clamping jaw 7 is in the rest position PO, said clamping jaw 7 remains contained inside a fictitious envelope which is centered on the central axis Z1 and whose radius, considered in a plane normal to the central axis Z1, is obtained by applying to the radius of the receiving surface 2, considered in said plane normal to the central axis Z1, a transformation by a homothety centered on the central axis Z1 and whose homothety ratio is equal to or less than 105%, preferably equal to or less than 102%, or even preferentially equal to or less than 101%, possibly equal to or less than 100.5%.Said fictitious envelope therefore has the same general shape as the real receiving surface 2 (for example a straight cylinder, or a slightly curved barrel shape), but with a radius, or radii if the radius varies along the central axis Zl, which is slightly greater than the corresponding radius, or radii, of the receiving surface 2.

[0068] In other words, the thickness by which the clamping jaw 7, in the rest position PO, possibly projects radially beyond the receiving surface 2 represents less than 5%, preferably less than 2%, or even less than 1%, possibly less than 0.5% of the radius of the receiving surface 2 at the abscissa considered along the central axis Zl.

[0069] For information purposes, the radial excess thickness provided by the clamping jaw 7, in the rest position PO, relative to the receiving surface 2, is preferably equal to or less than 4 mm, 3 mm or even 1.5 mm.

[0070] The radius of the receiving surface 2 may be, for example, between 300 mm and 400 mm, and in particular equal to 350 mm + / - 20 mm, in particular in the area occupied by the clamping jaw 7 in the rest position PO.

[0071] Here again, this allows the fixing device 5 to remain compact and discreet, and prevents the clamping jaw 7, when it is in the rest position PO, from hindering access to the receiving surface 2 or from creating an unbalance or a protruding obstacle on the drum 1 which could interfere with an object external to the drum 1 during rotation of the receiving surface 2.

[0072] Such an arrangement makes it possible in particular, after having placed on the drum 1 a first constituent element of the bandage 3 forming a reinforcement belt, then retracted the clamping jaw 7 into the rest position PO, to safely place a tread, forming a second constituent element of the bandage, over said reinforcement belt.

[0073] The FWD engagement movement which allows moving from the rest position PO to the working position PI is preferably carried out along the same spatial trajectory T7 as the BWD disengagement movement, simply by following said trajectory T7 in the opposite direction.

[0074] The FWD engagement movement thus also includes at least one centripetal FWD R2 radial component, particularly in the final phase of the FWD engagement movement.

[0075] This centripetal radial component FWD R2 advantageously allows the clamping jaw 7 to approach the external radial face 3_out of the constituent element of the bandage 3 according to a quasi-radial, or even exactly radial, approach, which guarantees the application of a radial clamping force F clamp and therefore a radial compression of the constituent element of the bandage 3, without risk of causing an undesirable axial or circumferential sliding of said constituent element of the bandage 3 relative to the receiving surface 2.

[0076] It will be noted that, if, like the BWD disengagement movement, the FWD engagement movement follows a concave, quasi-parabolic trajectory T7, then said FWD engagement movement will comprise, in combination with an axial component FWD A which axially brings the clamping jaw closer to the desired area on the receiving surface 2, a first centrifugal radial component FWD R1, in the initial phase of the FWD engagement movement, then a second centripetal FWD R2 radial component in the final phase of said FWD engagement movement.

[0077] Preferably, the drum 1 is subdivided into a plurality of tiles 12 which are distributed in azimuth around the central axis ZI so as to form, as a whole, the receiving surface 2.

[0078] In a manner known per se, and as can be seen in figures 1A, 1B and 2, such tiles 12 may have edges forming combs, so as to be able to fit into one another, in such a way that said tiles 12 ensure the continuity of the receiving surface on the circumference of the drum 1 while having relative mobility between neighboring tiles.

[0079] Advantageously, this relative circumferential mobility, in combination with a radial expansion / retraction mechanism, makes it possible to modify the radial position of said tiles 12, and consequently the diameter of the drum 1, and more particularly the diameter and therefore the circumference of the receiving surface 2, and consequently the winding diameter of the constituent element of the bandage 3, depending on the dimensions of the bandage to be manufactured.

[0080] Preferably, the fixing device 5 is integrated into one of said tiles 12.

[0081] More particularly, the base 6 can be fixed, reversibly, for example by screwing, in a housing 13 which is hollowed out on the radially internal face of the tile 12, while the radially external face of said tile 12 forms a portion of the receiving surface 2.

[0082] Furthermore, at least a portion of the actuating mechanism 10 is preferably contained in said housing 13, radially set back from the receiving surface 2.

[0083] The fixing device 5 is thus particularly compact, since said fixing device 5 is at least partly contained in the (radial) thickness of the tile 12 itself, and more generally at least partly, or even almost entirely, contained inside the envelope that the receiving surface 2 radially delimits around the central axis Z 1.

[0084] Preferably, the fixing device 5 is located on the axially external lateral edge of the tile 12, that is to say on the free edge of the tile 12, which corresponds to the edge of said tile 12 which is axially furthest from the plane called the “equatorial plane” PE of the drum. The equatorial plane PE of the drum is the plane which is normal to the central axis ZI and located at mid-width of the drum 1, that is to say axially at an equal distance from each of the axial ends of the drum 1, and more particularly at an equal distance from each of the axial ends of the receiving surface 2.

[0085] Thus, by being placed at the edge of the tile 12, and more generally at the edge of the drum 1, the fixing device 5 does not clutter the receiving surface 2 and can easily retract the clamping jaw 7 into a rest position PO which is located at a free axial end of the receiving surface 2, axially away from the central zone of said receiving surface 2.

[0086] Advantageously, when it is in the rest position PO, the clamping jaw 7 remains contained axially in the overall axial range occupied by the drum 1, and more particularly in the overall axial range occupied by the receiving surface 2, so that said clamping jaw 7 does not form an axial projection relative to the lateral edges of the drum 1, and more particularly relative to the receiving surface 2, and in particular relative to the axially outermost edge of the tile 12 which carries said fixing device 5.

[0087] Thus, by fitting into the axial envelope of the drum 1, and more particularly of the receiving surface 2, said fixing device 5 has good compactness, and reliable and safe operation, in that it does not risk, during the rotational movement of said drum 1 around the central axis Zl, colliding with an object which would be axially close to the drum 1.

[0088] According to a preferred characteristic of the fixing device 5 which may constitute an invention in its own right, adaptable in particular to different types of supports for manufacturing bandages, other than drums 1, the actuating mechanism 10 comprises, as is clearly visible in FIGS. 3 to 8, an articulated quadrilateral 20 of which a first vertex and a second vertex are formed respectively by a first pivot 21 belonging to the base 6 and by a second pivot 22 belonging to the base 6, and of which a third vertex and a fourth vertex are formed respectively by a third pivot 23 and by a fourth pivot 24 which both belong to a platform 25 which carries the clamping jaw 7.

[0089] In a reference frame attached to the base 6, and therefore attached to the receiving surface 2, the base 6 therefore forms a fixed base, and the platform 25 a mobile platform 25 designed to alternately reach on the one hand a first position (figure 4, figure 8), which corresponds to a position in which the clamping jaw 7 fixed on said platform 25 is in the rest position PO, and on the other hand a second position (figure 3, figure 5) in which the clamping jaw 7 fixed on the platform 25 is in the working position PI.

[0090] Advantageously, an articulated quadrilateral structure 20 according to the invention is particularly simple and robust, and makes it possible to give the clamping jaw 7 a concave, quasi-parabolic trajectory T7, which provides the advantages described above.

[0091] The respective axes Z21, Z22, Z23, Z24 of the first, second, third and fourth pivots 21, 22, 23, 24 are parallel to each other.

[0092] This allows the deformation of the articulated quadrilateral 20 in a plane, here a radial plane containing the central axis ZI of the drum 1

[0093] More particularly, the axes Z21, Z22, Z23, Z24 of the first, second, third and fourth pivots 21, 22, 23, 24 are all normal to the same radial reference plane, called the “sagittal plane” PS, which contains the central axis ZI of the drum 1 and which subdivides the drum 1 into two parts which are substantially symmetrical to each other.

[0094] By convention, said sagittal plane PS preferably corresponds to the radial plane which contains on the one hand the central axis ZI and on the other hand the radius perpendicular to the central axis ZI and which corresponds to the bisector which divides into two equal angular sub-sectors the angular sector which the tile 12 covers, in azimuth, around the central axis Zl.

[0095] Furthermore, the first, second, third and fourth pivots 21, 22, 23, 24 are advantageously distinct from one another and not coaxial with one another, so that the vertices of the articulated quadrilateral 20 are distinct and distant from one another.

[0096] It will also be noted that the first pivot 21 is radially closer to the central axis Zl than the third pivot 23 and that, likewise, the second pivot 2 ... closer to the central axis ZI than the fourth pivot 24. The first pivot 21 is here also radially closer to the central axis ZI than the second pivot 22.

[0097] As is clearly visible in Figures 3, 4, 5, 6, 7 and 8, the platform 25 is preferably connected to the base 6 by means of, on the one hand, a first arm 26 which connects the first pivot 21 to the third pivot 23, thus defining a first side 26A of the articulated quadrilateral 20, and on the other hand, a second arm 27 which connects the second pivot 22 to the fourth pivot 24, thus defining a second side 27A of the articulated quadrilateral 20.

[0098] It will be noted that, whatever the shape of the first arm 26 which is used to physically connect the first pivot 21 with the third pivot 23, the term "first side" 26 A will designate the straight line segment which, geometrically, joins the first pivot 21 to the third pivot 23, and more particularly the straight line segment which is perpendicular and intersecting the axes Z21 of the first pivot 21 and Z23 of the third pivot 23 and which thus joins, in the aforementioned sagittal plane PS, the center of rotation of the first pivot 21 to the center of rotation of the third pivot 23, that is to say which joins the first vertex of the articulated quadrilateral 20 to the third vertex of the articulated quadrilateral 20.

[0099] Similarly, the term “second side” 27A designates the straight line segment which, whatever the material form of the second arm 27, geometrically joins the second vertex of the articulated parallelogram 20, therefore the center of rotation of the second pivot 22, to the fourth vertex of the articulated parallelogram 20 formed by the center of rotation of the fourth pivot 24.

[0100] It will be noted that the shape of the first arm 26, respectively the shape of the second arm 27, can vary without departing from the scope of the invention.

[0101] That being said, for simplicity of construction, the first arm 26 and the second arm 27 will preferably be rectilinear.

[0102] Preferably, the first arm is formed by a connecting rod, or a pair of connecting rods parallel to each other, which each connect the first pivot 21 to the third pivot 23. Similarly, the second arm 27 is formed by a connecting rod, or a pair of connecting rods parallel to each other, which each connect the second pivot 22 to the fourth pivot 24.

[0103] The housing 13, hollowed out in the tile 12 to accommodate the base 6 and at least part of the actuating mechanism 10, will preferably be through-hole so as to open onto the radially external face of the tile 12, in order to allow the passage of the first and second arms 2627 as well as the travel of said arms 26, 27 and of the platform 25 during the FWD engagement and BWD disengagement movements. Preferably, the housing 13 will thus form a notch cut into the axially outermost edge of the tile 12.

[0104] It will be noted that the fixing device 5 will preferably be arranged in such a way that, both in the rest position PO and in the working position PI, the first and second arms 26, 27, as well as the radially outermost surface of the platform 25, on which the clamping jaw 7 is fixed, are located radially set back from the radially outer face of the tile 12, that is to say are closer to the central axis ZI than the radially outer face of the tile 12, so as to be re-entrant relative to the apparent surface of said tile 12 and to the receiving surface 2. Here again, this arrangement will contribute to the compactness of the fixing device 5.

[0105] The first arm 26 gives the first side 26 A a fixed length L26A, that is to say establishes an invariant distance between the first pivot 21 and the third pivot 23, that is to say that said first arm 26 maintains a center distance of constant value between the first pivot 21 and the third pivot 23. Thus, the length L26 A of the first side 26 A will be constant during the FWD engagement and then BWD disengagement movements.

[0106] This being the case, a fixed adjustment system may be provided to modify, before implementing said FWD engagement and then BWD disengagement movements, the length L26A of the first side, in order to adjust the desired center distance between the first pivot 21 and the third pivot 23. For this purpose, the first arm 26 may, for example, have a telescopic structure, of adjustable length, lockable at the desired length by any means such as a screw.

[0107] The same will apply to the second arm 27 which will define a length L27A of the second side 27 A, that is to say the center distance separating the second pivot 22 from the fourth pivot 24, which will be fixed, possibly adjustable by an adjustment system.

[0108] Such an adjustment system will, among other things, advantageously allow the working position PI to be adapted as a function of the thickness E3 of the constituent element of the bandage 3 which it is desired to maintain by clamping on the receiving surface 2.

[0109] Particularly preferably, the length of the second side L27A, that is to say, as indicated above, the distance which separates the axis Z24 of the fourth pivot 24 from the axis Z22 of the second pivot 22, is smaller than the length of the first side L26A, that is to say, as indicated above, the distance which separates the axis of the third pivot 23 from the axis of the first pivot 21: L27A < L26A

[0110] In other words, the second arm 27 is shorter than the first arm 26.

[0111] Thanks to this difference in length between the first arm 26 and the second arm 27, the articulated quadrilateral 20 forms a “false parallelogram”, which advantageously makes it possible to combine with the generally parabolic trajectory T7 mentioned above, during the release movement BWD, a tilting component BWD P of the clamping jaw 7, in pitch around the circumferential direction XI.

[0112] This tilting in pitch BWD P, which occurs from the start of the release movement BWD, advantageously makes it possible to detach the clamping jaw 7 from the radially external face 3_out of the constituent element of the bandage 3 resting on the receiving surface 2 without the clamping jaw 7 exerting friction, and therefore axial traction, on said constituent element of the bandage 3.

[0113] Thus, there is no risk of accidentally moving the front end portion 3F of said constituent element of the bandage 3 when the clamping jaw 7 leaves its working position PI to reach its rest position PO.

[0114] Such an arrangement using arms 26, 27 of different lengths also has the advantage of accentuating the radial nature of the approach orientation during the final phase of the FWD engagement movement, and thus promotes the generation of a high intensity radial clamping force F clamp.

[0115] It will be noted that the shorter arm, here the second arm 27, and therefore the second and fourth pivots 22, 24, are axially closer to the portion of the receiving surface 2 which receives the constituent element of the bandage 3 than the longer arm, here the first arm 26, and the first and third pivots 21, 23.

[0116] Equivalently, the first and third pivots 21, 23, as well as the first arm 26 (long arm), are therefore axially further from the equatorial plane PE of the drum 1 than are, on the same side of said equatorial plane PE, the second and fourth pivots 22, 24 and the second arm 27 (short arm).

[0117] The actuating mechanism 10 can be powered by any type of motor, electric, pneumatic, or hydraulic.

[0118] Preferably, the actuating mechanism 10 is driven by a jack 30, for example a double-acting pneumatic jack, the body 31 of which is carried by the base 6 and the rod 32 of which engages on the first arm 26, at the level of a fifth pivot 33 by which said rod 32 is articulated on said first arm 26. This fifth pivot 33 is located between the first pivot 21 and the third pivot 23, at a distance from each of said first and third pivots 21, 23.

[0119] The axis Z33 of this fifth pivot 33 is further parallel to the axes Z21, Z22, Z23, Z24 of the first, second, third and fourth pivots 21, 22, 23, 24.

[0120] Advantageously, such a very compact arrangement allows the jack 30 to cause the tilting of the first arm 26, and therefore the deformation of the articulated quadrilateral 20 and consequently the displacement of the platform 25 and the clamping jaw 7, alternately in a direction corresponding to the engagement movement FWD, here, in Figures 5 to 8, by tilting the first arm 26 clockwise, retracting the rod 32 into the body 31 towards the right, then in an opposite direction corresponding to the release movement BWD, here, in Figures 5 to 8, by tilting the first arm 6 counterclockwise, deploying the rod 32 out of the body 31 towards the left.

[0121] Preferably, in particular to promote the compactness of the fixing device 5, the fifth pivot 33 is radially further from the central axis ZI than the first pivot 21, and radially closer to said central axis ZI than the second pivot 22.

[0122] Preferably, the body 31 of the jack 30 is articulated on the base 6 at the level of a sixth pivot 34, the axis Z34 of which is parallel to the axis Z33 of the fifth pivot 33.

[0123] The jack 30 is preferably arranged substantially parallel to the central axis Zl, in the housing 13, opposite the radially internal face of the tile 32, so that the direction of translational movement of the rod 32 is parallel to the central axis Zl at + / - 10 degrees. The sixth pivot 34 is, for this purpose, preferably located axially closer to the equatorial plane PE than the fifth pivot 33. Such an arrangement makes it possible to reconcile compactness and power of the actuating mechanism 10.

[0124] According to a preferred characteristic of the fixing device 5, which may constitute an invention in its own right, adaptable to different types of actuating mechanisms 10, including of course the actuating mechanism 10 with articulated quadrilateral 20 described above, and / or adaptable to different types of bandage manufacturing support, whether said support is a drum 1 or other, the clamping jaw 7 is formed, as is clearly visible in FIGS. 3 and 4, by a leaf spring 40, which is arranged so as to be able to flex elastically under the stress of the clamping force F clamp.

[0125] Thus, the clamping jaw 7 is not only simple, light, compact and robust, but it also has a flexibility (“compliance” in English) which allows it to flex elastically in contact with the constituent element of the bandage 3, against the resistance opposed by the underlying receiving surface 2, under the clamping force F clamp.

[0126] The clamping action, which results from the forced application of the spring blade 40 against the constituent element of the bandage 3, under the action of the jack 30 transmitted through the actuating mechanism 10 (and in particular through the first arm 26 which forms a lever), thus adapts automatically to the thickness E3 and to the intrinsic compression rigidity of the constituent element of the bandage 3.

[0127] The leaf spring 40 is advantageously mounted flat on the platform 25, so that the thickness E40 of said leaf spring 40 is oriented in a radial direction Y1 (here the radial direction Y1 which, with the central axis Z1, generates the sagittal plane PS mentioned above), in order to allow a bending which has the effect of curving the leaf spring 40 around the circumferential direction XI, that is to say a bending which results from a bending moment which is carried by said circumferential direction XL.

[0128] For information purposes, the spring blade 40 may be made of steel, in particular a spring steel containing silicon, or even an aluminum-based alloy, or even a composite material. Preferably, the face of the spring blade 40, here the radially internal face of said spring blade 40, intended to come into contact with the constituent element of the bandage 3, here therefore intended to come into contact with the radially external face 3_out of said constituent element of the bandage 3, may be coated with a non-stick material, such as Xylan®.

[0129] Preferably, the spring blade 40 may have a thickness of between 0.5 mm and 3 mm, for example between 1 mm and 2 mm.

[0130] This relative thinness will not only make it possible to give the spring blade 40 good flexibility and suitable flexural elasticity, but also to minimize the radial size of said spring blade 40, in order to limit, when the clamping jaw 7, and therefore here the spring blade 40, occupies the working position PI, the interferences between said spring blade 40 and the guiding and positioning members responsible for conveying the constituent element of the bandage 3 to the drum 1 and for positioning and guiding said constituent element of the bandage 3 relative to the drum 1 during the winding operation.

[0131] In particular, the small thickness of the spring blade 40 limits the radial height of the possible projection that said spring blade 40 forms on the receiving surface 2 in the working position 1P1 and thus allows an applicator roller, intended to apply the constituent element of the bandage 3 to the drum 1, to roll on the receiving surface 2 in the circumferential direction XI and to cross the location occupied by the spring blade 40, and therefore to cross said projection, passing partly over the spring blade 40, without damage either to said applicator roller, or to the constituent element of the bandage 3, or to the spring blade 40.

[0132] In this respect, it will even be possible, according to one possible arrangement, to chamfer or round the lateral edges of the radially external face of the spring blade 40, edges which are here parallel to the central axis Zl, in order to form ramps which will facilitate the crossing of said edges, by the applicator roller, in the circumferential direction XI.

[0133] Preferably, as is clearly visible in figures 3, 5, 6, 7 and 8, the spring blade 40 is mounted in a cantilever manner so as to have on the one hand a captive portion 40A, fixed in abutment on the platform 25, and on the other hand a free end portion 40B which projects axially relative to the platform 25 so as to be able to come into contact with the constituent element of the bandage 3 when the clamping jaw 7 is brought into the working position PI.

[0134] Here again, such an arrangement contributes to the lightness, simplicity, and robustness of the fixing device 5, while ensuring good flexibility of the clamping jaw 7.

[0135] Preferably, as is particularly clearly visible in Figure 3, the spring blade 40 comprises at least one slot 41 which extends axially over a portion of the length of said spring blade 40 so as to subdivide said spring blade 40 into at least two tabs 42, 43 which are each intended to come into contact with the constituent element of the bandage 3 when the clamping jaw 7 is in the working position PI, and which each occupy a different angular sector around the central axis Zl.

[0136] Advantageously, the subdivision into tabs 42, 43 makes it possible to reduce the rigidity, and therefore to increase the flexibility, of the leaf spring 40, while retaining a thickness E40 sufficiently large to allow the leaf spring to resist plasticization under the clamping force F clamp, that is to say to allow the leaf spring 40 not to undergo irreversible plastic deformation when said leaf spring 40 is pressed against the constituent element of the bandage 3.

[0137] The presence of at least one slot 41 consequently improves the flexibility of the fixing device 5, compared to a spring blade 40 which would be solid over its entire width, considered in the circumferential direction XI, that is to say which would be solid over the entire circumferential portion of the receiving surface 2 that said spring blade 40 covers, around the central axis Zl, when said spring blade 40 is in the working position PI.

[0138] Furthermore, the subdivision into at least two tabs 42, 43 makes it possible to dedicate each of said tabs 42, 43 to a specific angular sector around the central axis Zl, each tab 42, 43 thus generating its own support on the constituent element of the bandage 3, independently of the other tab 43, 42, which allows the clamping jaw 7, here the spring blade 40, to better match, by a double support, the curvature of the drum 1, considered in a plane normal to the central axis Zl.

[0139] Preferably, as can be seen in Figures 3 and 4, the slot 41 extends axially to the axial end of the free end portion 40B of the spring blade 40. The at least two tabs 42, 43 thus form terminal tabs 42, 43 of which the respective axial ends are free, and in particular free to flex independently of one another.

[0140] According to such an arrangement, the at least two tabs 42, 43 form the free end portion 40B, while they are attached to, and in this case formed in a single piece with, the same common root which in turn forms the captive portion 40A fixed to the platform 25.

[0141] Of course, the invention also relates as such to an installation 50 for manufacturing a bandage comprising: - a 51 frame, - a drum 1 according to any one of the possible variants of the invention, said drum 1 being mounted in rotation relative to the frame 51 so as to be able to rotate on itself around its central axis Zl, - at least one supply system 52 arranged to convey to the drum 1 a constituent element of the bandage 3 which is in the form of a strip 4, so that the front end portion 3F of the strip 4 delivered by the supply system 52 can be fixed on the receiving surface 2 of the drum 1 by means of the fixing device 5, then said strip 4 can be wound over at least one complete turn, and preferably over several complete turns, around the central axis Z 1, on the receiving surface 2, by setting the drum 1 in rotation around its central axis Zl.

[0142] In a manner known per se, the driving of the drum in rotation relative to the frame 51, which makes it possible to wind each strip 4 and thus close it in a ring on itself around the central axis Zl, can be carried out by an electric motor.

[0143] The supply system 52 can be formed for example by a reel which receives a reel where the strip 4 is stored, which is then unwound from said reel as said strip is wound onto the drum 1, or even by a calender which continuously produces the strip 4, in the desired quantity, by passing simultaneously between two rollers, which define an air gap corresponding to the thickness E3 of the strip 4, reinforcing threads as well as two thin layers of rubber which sandwich said reinforcing threads.

[0144] As indicated above, the supply system 52 may include guide and placement members (not shown), in particular an applicator roller, which make it possible to guide the strip 4 and to apply said strip 4 to the receiving surface 2 of the drum 1.

[0145] Furthermore, the fixing device 5, and more generally the drum 1 and therefore the installation 50 for manufacturing a bandage, preferably comprises a set of interchangeable clamping jaws 7, in the form of a set of several spring blades 40 of different lengths, in order to be able to adapt the clamping device 5 as a function of the axial position and / or the axial width W3 of the constituent element of the bandage 3 that it is desired to maintain on the drum 1.

[0146] Thanks to this plurality of removable and interchangeable spring blades 40, the fixing device 5, and more generally the drum 1 thus equipped, therefore presents great versatility, because it can adapt to numerous models and dimensions of bandages.

[0147] Preferably, several of the leaf springs 40, or even all of the leaf springs 40, are split to have tabs 42, 43 as described above.

[0148] The invention also relates to a method for manufacturing a bandage during which a front end portion 3F of a constituent element 3 of the bandage 3, here a strip 4, is held on a drum 1 according to the invention, by means of the fixing device 5 carried by said drum 1, while said constituent element 3 of the bandage, here the strip 4, is wound onto said drum 1.

[0149] Preferably, during this method of manufacturing a bandage, the constituent element of the bandage 3, here the strip 4, is wound from the front end portion 3F of said constituent element of the bandage which forms the starting point of a first turn, in several consecutive helical turns, including at least a second turn which follows the first turn.

[0150] Said consecutive helical turns are axially offset from one another, so that said turns do not axially overlap the front end portion 3F of the constituent element of the bandage 3, or, at most, only partially overlap, axially, said front end portion 3F.

[0151] According to this same method, the size of the clamping jaw 7 is chosen, here the axial length of the spring blade 40, in such a way that, when said clamping jaw 7 is in the working position PI to hold the front end portion 3F on the receiving surface 2 of the drum 1, the clamping jaw 7 is interrupted axially before the axial range which is occupied by the second turn and the following turns, so that no turn comes to cover and trap said clamping jaw 7.

[0152] Advantageously, the clamping jaw 7, here the spring blade 40, is in no way jammed by the turns of the constituent element of the bandage 3, since said clamping jaw 7 is placed on the first turn but is interrupted axially before the edge of the second turn, the clamping jaw 7 can then be removed, in order to make it leave its working position PI and return it to its rest position PO, without disturbing or damaging the annular block formed by all of said turns.

[0153] The operation of the fixing device according to the invention will now be briefly described with reference to Figures 5, 6, 7 and 8.

[0154] Initially (figure 8), the clamping jaw 7, which will be assimilated for convenience to a spring blade 40 in what follows, is in the rest position PO, outside the area of ​​the receiving surface 2 where the constituent element of the bandage 3 will be positioned. For convenience of description, said constituent element of the bandage 3 will be assimilated to a band 4 in what follows. The drum 1 is stationary.

[0155] The spring blade 40 carried by the platform 25 is selected, and if necessary replaced, so as to adapt the fixing system 5 to the bandage that is to be manufactured. If necessary, the fixed settings of the actuating mechanism 10 are also adjusted by means of the adjustment system, here in particular the respective fixed lengths L26A, L27A of the first and second arms 26, 27 of the articulated quadrilateral 20.

[0156] Once the fixing system 5 is ready, the supply system 52 delivers at least a portion of the strip 4, the front end portion 3F of which is applied to the receiving surface 2, in the desired starting position. This starting position is such that it at least partly overlaps the working position PI such that this working position is defined by the range of the stroke of the actuating mechanism 10 of the fixing system 5 and by the dimensions of the chosen leaf spring 40.

[0157] The activation of the jack 30 is then controlled by an appropriate control unit, so that the jack 30 actuates its rod 32, here retracts said rod 32 into the body 30, and thus causes the tilting, here clockwise in Figures 7, 6 and 5, of the first arm 26.

[0158] This forced tilting of the first arm 26 induces a deformation of the articulated quadrilateral 20 around its pivots 21, 22, 23, 24, and is thus converted into a concave, quasi-parabolic curved movement of the platform 25 and therefore of the spring blade 40 carried by said platform 25, relative to the central axis Zl.

[0159] During the first phase (transition from figure 8 to figure 7) of the FWD engagement movement, corresponding to the ascending phase of the quasi-parabolic trajectory T7, the spring blade 40 lifts radially according to the first radial component FWD R1 centrifugal and begins to progress according to an axial component FWD A, directed towards the equatorial plane PE of the drum, until reaching the apogee of its trajectory T7, corresponding to the position shown in figure 7.

[0160] Preferably, the actuating mechanism 10 is arranged such that, at this apogee, the first arm 26 and the second arm 27 are both, simultaneously, radially stretched, that is to say that the third pivot 23 is located radially vertically above the first pivot 21 and the fourth pivot 24 is radially vertically above the second pivot 22. This choice of configuration at the apogee of the trajectory T7, which corresponds substantially to a position located midway between the rest position PO and the working position PI, makes it possible in particular to maintain relative parallelism between the leaf spring 40 and the receiving surface 2 in each of the two useful extreme positions of the trajectory T7, namely the rest position PO and the working position PI.

[0161] The FWD engagement movement continues with a descending phase of the quasi-parabolic trajectory T7, combining an axial component FWD A directed towards the equatorial plane PE and a second radial component FWD R2, this time centripetal, which allows the leaf spring 40 to fold back towards the central axis Zl and therefore towards the receiving surface 2, and thus to gradually approach the strip 4 (figure 6), and more precisely the radially external face 3_out of said strip 4, until reaching the working position PI, in which said leaf spring 40 is pressed against said strip 4 (figure 5).

[0162] The traction exerted on the rod 32 of the jack 30 then results in a substantially radial clamping force F clamp, which presses the strip 4 against the receiving surface 2, at the desired location to form the starting point of the winding.

[0163] It will be noted that, advantageously, the difference in length between the first arm 26 and the second arm 27 creates, during the downward phase of the FWD engagement movement, a pitch tilting FWD P of the leaf spring 40, here in the clockwise direction around the circumferential direction XI in FIGS. 6 and 5, pitch tilting which folds back the free end portion 40B, split, of the leaf spring 40, and thus promotes the application of said leaf spring 40 on the radially external face 3_out of the strip 4 in a quasi-radial direction, and therefore quasi-normal to the receiving surface 2, without generating any unwanted axial movement of said strip 4 on the receiving surface 2.

[0164] Furthermore, the flexibility of the spring blade 40 allows said spring blade 40 to deform elastically in contact with the strip 4 supported by the receiving surface 2, and thus to flexibly adapt the clamping force F clamp and the distribution of the clamping according to the geometry and dimensions of the drum 1 and the strip 4.

[0165] Once the strip 4 is locked onto the receiving surface 2 by the fixing device 5 (figure 5, figure 1A), the rotation of the drum 1 around the central axis Zl is started.

[0166] The fixing device 5 is driven integrally with the drum 1 in this rotational movement, and, because said fixing device 5 firmly holds the strip 4 in the chosen position on the circumference of the drum 1, the strip 4 is driven, by longitudinal traction, in the circumferential direction XI, and therefore begins to wind onto the drum 1.

[0167] The drum rotation continues as long as necessary to create the desired number of turns of band 4 on drum 1.

[0168] Preferably, this rotation of the drum 1 is accompanied by a relative axial displacement of the supply system 52, and more particularly of the applicator roller, relative to the drum 1, parallel to the central axis Zl, in order to generate a helical winding, over several turns, having the desired pitch.

[0169] Once the winding of the strip 4 is complete, the rotation of the drum 1 is stopped, then the fixing device 5 is actuated again, this time to release the strip 4, by carrying out the release movement BWD.

[0170] Optionally, before carrying out the release movement BWD, it will be possible to temporarily keep the clamping jaw 7 in the working position PI for the time necessary for a reconfiguration of the drum 1, and more generally for the time necessary for a reconfiguration of the installation 50, with a view to carrying out a second winding operation intended to place on the drum 1, over the band 4 placed during the first winding operation, another constituent element of the bandage 3.

[0171] For example, it will thus be possible to keep the clamping jaw 7 in the working position PI for the time necessary to transfer the drum 1 carrying the strip 4 from the manufacturing station where the operation of winding the strip 4 took place to another distant manufacturing station, designed to carry out another winding operation intended to place on the drum 1, over the strip 4, another constituent element of the bandage 3. According to another example, it will be possible to keep the clamping jaw 7 in the working position PI for the time necessary to reorient the drum 1 in azimuth around the central axis Zl, within the manufacturing station which has already been used to wind the strip 4, in order to define the starting position from which it is desired to wind the new constituent element of the bandage 3 over the strip 4 already in place.The clamping jaw can even be kept in the working position PI until the start of the installation, over the strip 4, of the new constituent element of the bandage 3.

[0172] To carry out the BWD release movement, the rod 32 of the cylinder 30 is deployed to tilt the first arm 26 in the opposite direction to the direction previously used for the FWD engagement movement, here therefore in an anti-clockwise direction in figures 6 to 8.

[0173] The return trajectory T7 corresponding to the BWD disengagement movement is identical to that of the FWD engagement movement, but is traveled in the opposite direction.

[0174] Thus, we find a concave, quasi-parabolic curved trajectory T7, comprising a first ascending phase (figures 6 and 7) during which we combine a pitch tilt BWD P, a first radial component BWD R1 centrifugal, and an axial component BWD A of recoil, in the direction of a move away from the equatorial plane PE, which allows the spring blade 40 to be detached and moved away from the strip 4. Advantageously, the spring blade 40 detaches and withdraws from the strip 4 without exerting any friction, or therefore any axial or circumferential traction, on the strip 4.

[0175] This recoil trajectory T7 then comprises, once past the apogee (figure 7), a descending phase (figures 7 and 8), which combines an axial component BWD A of recoil and a second radial component BWD R2 this time centripetal radial, and which makes it possible to return the leaf spring to the folded position against the tile 12, in its rest position PO (figure 8). The installation 50 thus offers a clear field for accessing the receiving surface 2 carrying the wound strip 4, either so that another constituent element of bandage 3 can be placed over said wound strip 4, or so that the annular block thus formed by said wound strip 4 can be removed from the drum 1.

[0176] Of course, the invention is in no way limited to the embodiment variants set out in the foregoing, the person skilled in the art being able in particular to isolate or freely combine one or other of the aforementioned characteristics, or to substitute equivalents for them.

[0177] In particular, it is possible to adapt to any type of application a fixing device 5 comprising an articulated quadrilateral 20, carried by a base 6, as well as a leaf spring 40, in particular with a split leaf spring 40, whatever the manufacturing support for which said fixing device 5 is intended, and on which it is fixed.

Claims

CLAIMS 1. Drum (1) for manufacturing a bandage, said drum (1) having a central axis (Zl) and having a radially external surface (2), called the "receiving surface" (2), which extends along and around said central axis (Zl) and which is intended to receive at least one constituent element of said bandage (3), said drum comprising a fixing device (5) which is intended to hold said constituent element of the bandage (3) on said receiving surface (2), said drum being characterized in that the fixing device (5) comprises: - a base (6) which is fixed to the drum (1), so that the fixing device (5) is carried by said drum (1), - a clamping jaw (7) which is arranged to adopt a position called the “working position” (PI), in which said clamping jaw (7) bears on a radially external face (3_out) of the constituent element of the bandage (3) while an opposite face, forming a radially internal face (3_in), of said constituent element of the bandage (3) rests on the receiving surface (2), in order to exert on said constituent element of the bandage (3) a radial compression force, called the “clamping force” (F clamp), which holds said constituent element of the bandage (3) on said receiving surface (2); - an actuating mechanism (10), which is carried by the base (6) and which connects the clamping jaw (7) to said base (6), said actuating mechanism (10) being arranged to cause the clamping jaw (7) to execute, relative to the base (6) and therefore relative to the receiving surface (2), alternately a first movement (FWD), called "engagement movement" (FWD), which makes it possible to bring the clamping jaw (7) from a rest position (PO) to the working position (PI), and a second movement (BWD), called "release movement" (BWD), which makes it possible to return the clamping jaw (7) to the rest position (PO) by moving the clamping jaw (7) back from the working position (PI) both according to a radial component (BWD R1), in order to release the clamping force (F clamp), and according to an axial component (BWD A), in order to release the axial range (11) which is occupied, on the receiving surface (2), by the constituent element of the bandage (3).

2. Drum according to claim 1 characterized in that the actuating mechanism (10) comprises an articulated quadrilateral (20) with a first apex and a second apex are formed respectively by a first pivot (21) belonging to the base (6) and a second pivot (22) belonging to the base (6), and of which a third vertex and a fourth vertex are formed respectively by a third pivot (23) and a fourth pivot (24) which both belong to a platform (25) which carries the clamping jaw (7), in that the respective axes (Z21, Z22, Z23, Z24) of the first, second, third and fourth pivots (21, 22, 23, 24) are parallel to each other, in that the platform (25) is connected to the base by means of on the one hand a first arm (26) which connects the first pivot (21) to the third pivot (23) thus defining a first side (26A) of the articulated quadrilateral (20) and on the other hand a second arm (27) which connects the second pivot (22) to the fourth pivot (24) in thus defining a second side (27 A) of the articulated quadrilateral (20), and in that the length (L27A) of the second side (27),that is to say the distance which separates the axis (Z24) of the fourth pivot from the axis (Z22) of the second pivot, is smaller than the length (L26A) of the first side (26), that is to say the distance which separates the axis of the third pivot (23) from the axis of the first pivot (21)., 3. Drum according to claim 2, characterized in that the actuating mechanism (10) is driven by a jack (30) whose body (31) is carried by the base (6) and whose rod (32) engages on the first arm (26), at the level of a fifth pivot (33) by which said rod (32) is articulated on said first arm (26) and which is located between the first pivot (21) and the third pivot (23), at a distance from each of said first and third pivots (21, 23).

4. Drum according to one of the preceding claims, characterized in that the clamping jaw (7) is formed by a spring blade (40), arranged so as to be able to flex elastically under the stress of the clamping force (F clamp).

5. Drum according to claim 4 and one of claims 2 or 3, characterized in that the spring blade (40) is mounted in a cantilever manner so as to have on the one hand a captive portion (40 A), fixed to bear on the platform (25), and on the other hand a free end portion (40B) which projects axially relative to the platform (25) so as to be able to come into contact with the constituent element of the bandage (3) when the clamping jaw (7) is brought into the working position (PI).

6. Drum according to one of claims 4 or 5, characterized in that the spring blade (40) comprises at least one slot (41) which extends axially over a portion of the length of said spring blade (40) so as to subdivide said spring blade (40) into at least two tabs (42, 43) which are each intended to come into contact with the constituent element of the bandage (3) when the clamping jaw (7) is in the working position (PI), and which each occupy a different angular sector around the central axis (Zl).

7. Drum according to one of the preceding claims, characterized in that it is subdivided into a plurality of tiles (12) which are distributed in azimuth around the central axis (Zl) so as to form, as a whole, the receiving surface (2), and in that the fixing device (5) is integrated into one of said tiles (12).

8. Installation (50) for manufacturing a bandage comprising: - a frame (51), - a drum (1) according to one of claims 1 to 7, said drum (1) being mounted in rotation relative to the frame (51) so as to be able to rotate on itself around its central axis (Zl), - at least one supply system (52) arranged to convey to the drum (1) a constituent element of the bandage (3) which is in the form of a strip (4), so that the front end portion (3F) of the strip (4) delivered by the supply system (52) can be fixed on the receiving surface (2) of the drum by means of the fixing device (5), then said strip (4) can be wound over at least one complete turn, and preferably over several complete turns, around the central axis (Zl), on the receiving surface (2), by setting the drum (1) in rotation around its central axis (Zl).

9. Installation according to claim 8 characterized in that it comprises a set of interchangeable clamping jaws (7), in the form of a set of several spring blades (40) of different lengths, in order to be able to adapt the clamping device (5) according to the axial position and / or the axial width (W3) of the constituent element of the bandage (3) which one wishes to maintain on the drum (1).

10. Method for manufacturing a bandage during which a front end portion (3F) of a constituent element (3) of the bandage is held on a drum (1) according to one of claims 1 to 7, by means of the fixing device (5) carried by said drum (1), while said constituent element (3) of the bandage is wound onto said drum (1).

11. Method according to claim 10, during which the element (3) constituting the bandage is wound, from the front end portion (3F) of the element constituting the bandage which forms the starting point of a first turn, in several consecutive helical turns, including at least one second turn which follows the first turn, consecutive helical turns which are axially offset from one another so that said turns do not axially overlap the front end portion (3F) of the element constituting the bandage, or at most only partially overlap, axially, said front end portion (3F), and during which the size of the clamping jaw (7) is chosen in such a way that, when said clamping jaw (7) is in the working position (PI) to hold the front end portion (3F) on the receiving surface (2) of the drum (1),the clamping jaw (7) is interrupted axially before the axial range which is occupied by the second turn and the following turns, so that no turn covers and traps said clamping jaw (7).,

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