Continuous manufacturing installation for a long, thin composite element

The installation addresses geometric imperfections in tubular composite bars by using a degassing, impregnation, and dual radiation process to achieve circular and concentric cross-sections at high speeds, ensuring isotropic properties and adaptability to existing facilities.

FR3167889A1Pending Publication Date: 2026-05-01MICHELIN & CO (CIE GEN DES ESTAB MICHELIN)
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Patent Information

Authority / Receiving Office
FR · FR
Patent Type
Applications
Current Assignee / Owner
MICHELIN & CO (CIE GEN DES ESTAB MICHELIN)
Filing Date
2024-10-25
Publication Date
2026-05-01

AI Technical Summary

Technical Problem

Existing manufacturing processes for tubular composite bars result in geometric imperfections such as elliptical cross-sections and non-concentric shapes, which are problematic for applications requiring precise geometry and isotropic properties.

Method used

A manufacturing installation that includes a degassing chamber, impregnation chamber, shaping device, and dual radiation stages to achieve partial and final polymerization, ensuring concentricity and circularity of the tubular bars by pre-polymerizing the composite elements to maintain shape and facilitate deformation before final polymerization.

Benefits of technology

The installation achieves tubular composite bars with precise circular and concentric cross-sections at high production speeds, maintaining mechanical properties while adapting to existing facilities.

✦ Generated by Eureka AI based on patent content.

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Abstract

A continuous manufacturing installation (100) for a long, thin composite element (FE) comprising a bundle of multifilament fibers impregnated with a polymerizable material composition, the installation (100) including a shaping device (120) configured to produce a tubular bar impregnated (E2) with the polymerizable material from the impregnated multifilament fibers (E1). The installation includes a first radiation device (117) for pre-polymerizing the impregnated tubular bar (E2) and a second radiation device (118) for performing a final polymerization of the pre-polymerized tubular bar (E3). Figure for the abbreviation: Fig 2
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Description

Title of the invention: Installation for the continuous manufacturing of a long, thin composite element

[0001] The present invention relates to the field of continuous manufacturing of long-line composite materials made by impregnating multifilamentary fibers with a polymerizable composition.

[0002] More particularly, the present invention relates to an installation for manufacturing composites in the form of tubular bars comprising continuous, unidirectional multifilamentary fibers embedded in a polymerizable resin.

[0003] The present invention relates more particularly, but not exclusively, to the manufacture of tubular bars made of glass resin composite, acronym "CVR", exhibiting high mechanical properties.

[0004] Such long-stretch composite materials can be used as composite reinforcements suitable, in particular, for reinforcing semi-finished products or finished rubber articles such as traction tracks, or in concrete reinforcement applications or for constructing structures.

[0005] We know of document EP 1 174 250 - Al which describes a continuous manufacturing process for single-strand CVR comprising the following steps:

[0006] - to create a rectilinear arrangement of glass fibers and to train this arrangement in a direction of advancement;

[0007] - degas the fiber arrangement by the action of a vacuum in a vacuum chamber;

[0008] - upon exiting the vacuum chamber, after degassing, passing through a chamber resin-filled impregnation device so as to impregnate said fiber arrangement with a resin in liquid state to obtain an impregnated material containing the fibers and the resin;

[0009] - passing said impregnated material through a calibration die having a cross-section of predefined surface and shape, to impose on it a single-strand form; and

[0010] - downstream of the calibration line, in an irradiation chamber, stabilize, solidify the monostrand by photopolymerizing the resin in a UV and / or IR radiation device

[0011] Experience shows, however, that the single-strand CVRs described can still be improved.

[0012] Generally, with reference to [Fig. 1], a device 1 for manufacturing a single strand of glass-resin composite comprises a plurality of reels 10 containing glass fibers 11 in the form of multifilaments, and each reel is continuously unwound or unspooled, without rotating the corresponding reel, by drive according the arrow F by a training means (not shown), so as to achieve a rectilinear arrangement 12 of these fibers 11.

[0013] The term “unwinding” means the action of emptying a spool by pulling on the wire in the direction of the spool's axis without rotating the spool.

[0014] The arrangement 12 then passes through a vacuum chamber 13 disposed between an inlet nozzle 13a and an outlet nozzle 13b and an impregnation chamber 14 downstream of the outlet nozzle 13b and filled with an impregnation composition 15 based on a curable resin. The device 1 further includes a calibration nozzle 16 at the outlet of the impregnation chamber 14 so as to form a single strand 17 and a radiation device 18 comprising, for example, a protective tube 18a through which the composite single strand 17 flows and a plurality of in-line UV irradiators 18b to obtain a polymerized single strand 19. The radiation device 18 further includes a nitrogen injection system (not shown).

[0015] Traditionally, known composite monostrands have, for example, a circular cross-section and are composed of continuous glass fibers impregnated with a polymerizable material, preferably photo-polymerizable.

[0016] However, in practice, in the case of tubular bars, the final geometry of the outer surface of the composite strand is not perfectly circular, but rather slightly elliptical, and the inner surface is neither perfectly circular nor perfectly centered with respect to the outer surface. Indeed, these geometric errors are a consequence of current manufacturing facilities and processes in which the composite strand exits the calibration die coated with a polymerizable material that is still in a liquid state before final polymerization. The composite strand therefore still has the possibility of changing its geometry before final polymerization sets its shape.

[0017] In some applications, a slight deformation of the elliptical geometry poses no problem, for example in concrete reinforcement applications. However, in other applications, a precise geometry is required, e.g., if the reinforcement is used in a rubber product manufactured in a mold where volume control is important.

[0018] Composite elements with a circular cross-section have the same physical properties in all directions, whereas those with an elliptical cross-section are anisotropic.

[0019] Thus, there is a need to remedy the aforementioned drawbacks.

[0020] The invention aims to improve the shape of the cross-section of a composite element, in particular tubular bars, while maintaining a high production speed, between 10m / min and 50m / min, preferably between 10m / min and 30m / min.

[0021] Furthermore, the present invention is designed to be easily adapted to existing composite element manufacturing facilities.

[0022] The present invention relates to an installation for the continuous manufacturing of a longline composite element comprising a bundle of multifilamentary fibers impregnated with a composition based on a polymerizable material, the installation comprising, in the direction of advancement of the bundle of multifilamentary fibers: - a feeding device configured to form a bundle of multifilamentary fibers; - a degassing chamber for the multifilament fiber bundle; - an impregnation chamber filled with a composition based on a polymerizable material and configured to impregnate said degassed multifilament fiber bundle with said composition and form impregnated multifilament fibers, said impregnation chamber being located downstream of the degassing chamber in the direction of advancement of the multifilament fiber bundle; - a device for shaping impregnated multifilament fibers configured to produce a tubular bar impregnated with polymerizable material from the impregnated multifilament fibers; - a first radiation device through which the impregnated tubular bar passes and configured to perform a partial polymerization of said impregnated tubular bar and to form a pre-polymerized tubular bar, and in particular, depending on the variant chosen, to guide the tubular bar to ensure good concentricity of the inner surface with respect to the outer surface or to deform the tubular bar in order to improve the outer surface of said bar while guiding it; and - at least one second radiation device, separate and distinct from the first radiation device configured to form a final composite element, and - a translational drive device configured to translate the multifilament fiber bundle and to apply a tension to said multifilament fiber bundle.

[0023] The shaping device includes an external part configured to form the outside diameter of the impregnated tubular bar and an internal part configured to form the inside diameter of the impregnated tubular bar.

[0024] The internal and external parts are coaxial and delimit between them an external conduit configured to receive the impregnated multifilament fibers, the internal part extending at least partly inside the first radiating device, so that when the impregnated tubular bar exits the external part of the shaping device, said impregnated tubular bar remains guided by the internal part.

[0025] The multifilament fibers entering the shaping device may be in the form of a bundle or at least two impregnated monostrands. In the following description, a bundle of several impregnated fibers or at least two impregnated monostrands will be referred to as a "bundle of impregnated fibers".

[0026] The first radiation device is configured to pre-polymerize, that is, to perform a partial polymerization of the impregnated tubular bar in order to stiffen said bar so that it retains its shape while preventing it from sticking to the inner part. The resin in contact with the inner part remains liquid, so that the frictional forces between the inner part and the bar remain low, allowing for a high production speed.

[0027] The second radiation device is configured to perform a final polymerization of the pre-polymerized tubular bar.

[0028] By "partial polymerization or pre-polymerization", it is meant that the degree of polymerization of the radiation-impregnated multifilament fiber bundle reached between 35% and 65% of complete polymerization.

[0029] By way of non-limiting example, the degree of polymerization can be evaluated using a "DSC" type measuring instrument, an acronym for "Differential Scanning Calorimetry" in Anglo-Saxon terms.

[0030] The pre-polymerization step makes it possible to obtain a pre-polymerized tubular bar, ideally non-sticky, capable of no longer deforming in the free state while being malleable, if necessary, to be deformed under mechanical stress.

[0031] The so-called “complete” or “final” polymerization of the composite is obtained when the degree of polymerization of the polymerizable material is close to 100%, preferably greater than or equal to 95% of the total polymerization.

[0032] Thanks to the shaping device, it is possible to give a circular and concentric shape to the cross-section of the pre-polymerized tubular bar before final polymerization. In other words, the aim is to obtain an inner radial surface of the bar that is concentric with the outer radial surface of the bar.

[0033] The circularity and concentricity of the cross-section of a composite tubular bar is thus improved, while maintaining a high production speed, between 10m / min and 50m / min, preferably between 10m / min and 30m / min.

[0034] Alternatively, a third ultraviolet light source could be added, positioned between the first radiating device and the final radiating device.

[0035] By "longitudinal composite element" is meant a long composite element comprising a bundle of multifilament fibers embedded in a composition based on a polymerizable material, which is manufactured continuously from one or more multifilament fiber feed reels for to form a bundle which is driven in translation to successively impregnate its fibers with polymerizable material and polymerize the material as the bundle moves.

[0036] By “multifilament fiber” is understood a fiber which comprises several elementary filaments arranged side by side to form a bundle whose elementary fibers are unidirectional by being substantially parallel to each other.

[0037] Multifilament fibers can be chosen from the group consisting of glass, carbon, silica, ceramic, flax, hemp, basalt, cellulose fibers, etc. These multifilament fibers are used to make long-strand composites made by impregnation with a polymerizable composition of the multifilament fibers.

[0038] The polymerizable material may be of the thermosetting type, preferably thermocrosslinkable, preferably of the vinylester type. By polymerizable material is meant a material comprising, by weight, more than 50%, preferably more than 75%, of organic matter and even more preferably more than 90% of organic matter.

[0039] Thus, this material can be a thermopolymerizable polymeric material, for example based on unsaturated polyester, polyepoxide, phenolic derivative, or aminoplast. Preferably, the polymerizable material is cross-linked.

[0040] For example, the polymerizable material is a resin crosslinkable by ionizing radiation, the final polymerization being able to be easily triggered and controlled by means of an ionizing treatment, for example of the UV type.

[0041] The glass transition temperature Tg of the polymerizable material is preferably greater than or equal to 130°C, for example greater than 170°C, preferably greater than or equal to 180°C.

[0042] For example, the final composite element is a hollow cylindrical monostrand, such as a tubular bar, with an outside diameter, for example, between 5mm and 50mm, preferably between 10 and 20mm, comprising multifilament fibers embedded in a polymerizable material, such as a thermosetting resin.

[0043] The elementary filaments each have, for example, an average diameter between 5pm and 30qm.

[0044] The translation drive device is, for example, of the type comprising a motorized traction drum allowing the composite element to be wound around its axis or comprising two opposing motorized bands facing each other, which press with a certain force on the final composite element, to drive it, by friction, in a translational movement, by making it pass into the space located between the two bands.

[0045] Advantageously, the external part of the shaping device is delimited axially by two lateral ends and radially by an external surface and a internal surface, and the internal part of the shaping device extends inside the external part over an axial length greater than the axial length of the external part.

[0046] In other words, the internal part extends axially beyond the lateral extremities of the external part.

[0047] Preferably, the upstream lateral end of the external part of the shaping device has an outside diameter greater than the outside diameter of the downstream lateral end and an inside diameter greater than the inside diameter of the downstream lateral end, so that the internal surface of the external part has an inclined slope from the upstream lateral end to the downstream lateral end over at least 10% of the total length of the external part.

[0048] According to another embodiment, the internal surface of the external part could be provided that it does not have such an inclined slope, but that the inlet of the external part could have a radius, either variable or fixed. The inclined slope is preferred when the external and internal parts are mechanically connected to each other by radial fins.

[0049] Thus, the conical shape or radius of the upstream lateral end allows the multifilament fibers to be inserted more easily into the outer part. Following the outer contour of the outer part to the inner contour of the outer part, in order to maintain the thinnest possible wall thickness, minimizes the material required for manufacturing the shaping device, particularly through three-dimensional printing techniques.

[0050] For example, the internal part of the shaping device is a hollow tube radially delimited by an external surface and an internal surface, the external surface delimiting with an internal surface of the external part the external conduit for receiving the impregnated multifilament fibers.

[0051] For example, the internal surface of the internal part of the shaping device delimits an internal conduit.

[0052] Said internal conduit allows air or nitrogen to circulate inside the impregnated tubular bar.

[0053] According to one embodiment, the internal and external parts of the shaping device are independent of each other and are not mechanically connected to each other.

[0054] In this embodiment, the shaping device includes a support for attaching the inner part, positioned upstream of the outer part. Thus, the impregnated fibers do not touch the support. This allows for a better flow of impregnated fibers into the outer part. In this embodiment, the inner and outer parts are also simple to manufacture.

[0055] According to another embodiment, the internal and external parts of the shaping device are independent of each other and mechanically connected to each other, for example by radial fins, for example two in number.

[0056] The shaping device can be made of resin, for example by three-dimensional printing techniques, or of metallic material, for example steel, for example by machining or three-dimensional printing techniques.

[0057] For example, the internal part of the shaping device has a length between 5cm and 1m, preferably between 30cm and 50cm.

[0058] For example, its length may be less than or equal to the length of the first radiating device.

[0059] According to one embodiment, the installation includes a pre-polymerized tubular bar guidance device disposed between the first radiation device and the second radiation device in the direction of advancement of the multifilament fiber bundle.

[0060] Said pre-polymerized tubular bar guidance device is configured to support the tubular bar and consequently the impregnated fibers in order to ensure that the internal part of the shaping device is located in the center of said impregnated fibers and / or to plastically deform the pre-polymerized tubular bar and to form a deformed tubular bar.

[0061] Said guiding device comprises at least one set of two shaping members, for example rollers, located one above the other in a direction perpendicular to the direction of advancement of the multifilament fiber bundle, on either side of the pre-polymerized tubular bar, the two shaping members being rotationally movable each around a transverse axis of rotation.

[0062] For example, the shaping elements each have the shape of a pebble with a generally cylindrical shape.

[0063] By "plastic deformation" is meant an irreversible deformation.

[0064] The transverse rotation axis is perpendicular to the direction of advancement of the multifilament fiber bundle.

[0065] For example, the transverse axis of rotation is perpendicular to and to the vertical axis.

[0066] According to one embodiment, the installation includes a heating device associated with the impregnation chamber and configured to heat the polymerizable material present in said impregnation chamber to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0067] Alternatively, it could be provided that the installation does not include such a heating device.

[0068] According to one embodiment, the first radiation device comprises a first light source comprising ultraviolet radiation, acronym UV.

[0069] The exposure time of the impregnated tubular bar to the first ultraviolet light source is between 0.1s and 1.5s, preferably between 0.4 and 0.7s

[0070] The power of the first combined UV light source is between 0.5kW and 14kW, preferably between 1kW and 5kW.

[0071] According to another embodiment, the first light source comprises a plurality of light-emitting diodes configured to emit only monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm, preferably between 365nm and 405nm.

[0072] According to another embodiment, the first light source comprises a plurality of mercury vapor lamps configured to emit broad-spectrum ultraviolet UV radiation, infrared radiation and visible light.

[0073] According to one embodiment, the second radiation device comprises a second light source with combined ultraviolet and infrared radiation or with infrared radiation alone to complete the polymerization of the pre-polymerized tubular bar.

[0074] The exposure time of the pre-polymerized tubular bar to the second light source combining ultraviolet and infrared rays is between 1s and 6s, preferably between 1.5s and 3s.

[0075] The power of the second UV and infrared light source is between 6kW and 60kW, preferably between 20kW and 40kW

[0076] According to one embodiment, the second light source comprises a plurality of light-emitting diodes, acronym LEDs, preferably directed radially towards the pre-polymerized tubular bar, the available wavelengths of which are between 200nm and 405nm, preferably between 365nm and 405nm. In this case, the LEDs are combined with infrared radiation.

[0077] According to another variant, the second light source could comprise a plurality of mercury vapor lamps, the exposure time of the pre-polymerized tubular bar being between 1s and 4s, preferably between 1.5s and 2s, at a power between 6kW and 60kW, preferably between 20kW and 40kW.

[0078] According to one embodiment, the second light source could comprise a plurality of mercury vapor lamps configured to emit broad-spectrum ultraviolet (UV) radiation, infrared radiation, and visible light. The mercury vapor lamps can be combined with infrared radiation with a wavelength between 1 pm and 3 pm.

[0079] According to yet another variant, the second radiating device could be provided to include a light source with infrared radiation only, configured to emit only infrared radiation, with a wavelength between Ipm and 3pm.

[0080] In this case, the exposure time of the pre-polymerized tubular bar to the second light source combining infrared radiation alone is between 2s and 8s, preferably between 3s and 4s and the power of this second infrared light source is between 10kW and 60kW, preferably between 20kW and 40kW.

[0081] Other objects, features and advantages of the invention will become apparent from the following description, given solely by way of non-limiting example, and made with reference to the accompanying drawings in which:

[0082] [Fig.1] represents, very schematically, a manufacturing installation for a composite element according to the state of the art;

[0083] [Fig.2] represents very schematically an installation for manufacturing a composite element according to an embodiment of the invention;

[0084] [Fig.3] represents very schematically a device for shaping the installation of the [Fig.2];

[0085] [Fig.4] illustrates in detail the shaping device of the [Fig.3];

[0086] [Fig.4A] is a longitudinal cross-sectional view of the shaping device of the [Fig.4];

[0087] [Fig.5] illustrates in detail the shaping device according to another embodiment;

[0088] [Fig.5A] is a longitudinal cross-sectional view of the shaping device of the [Fig.5].

[0089] Fig. 2 schematically illustrates an installation 100 for manufacturing a long, elongated EF composite element.

[0090] By "long-line composite element" is meant a long-length composite element comprising a bundle of multifilament fibers embedded in a composition based on a polymerizable material, which is manufactured continuously from several multifilament fiber feed reels Fi_0 to form a bundle which is driven in translation along the arrow F to successively achieve the impregnation of its fibers with polymerizable material and the polymerization of the material as the bundle moves.

[0091] By “multifilament fiber” is understood a fiber which comprises several elementary filaments arranged side by side to form a bundle whose elementary fibers are unidirectional by being substantially parallel to each other.

[0092] Multifilament fibers can be chosen from the group consisting of glass, carbon, silica, ceramic, flax, hemp, basalt, cellulose fibers, etc. These multifilament fibers are used to make long-strand composites made by impregnating the multifilament fibers with a polymerizable composition.

[0093] The polymerizable material may be of the thermosetting type, preferably thermocrosslinkable, preferably of the vinylester type. By polymerizable material is meant a material comprising, by weight, more than 50%, preferably more than 75%, of organic matter, and even more preferably more than 90% of organic matter.

[0094] Thus, this material can be a thermopolymerizable polymeric material, for example based on unsaturated polyester, polyepoxide, phenolic derivative, or aminoplast. Preferably, the polymerizable material is cross-linked.

[0095] For example, the polymerizable material is a resin crosslinkable by ionizing radiation, the final polymerization being able to be easily triggered and controlled by means of an ionizing treatment, for example of the UV type.

[0096] The glass transition temperature Tg of the polymerizable material is preferably greater than or equal to 130°C, for example greater than 170°C, preferably greater than or equal to 180°C.

[0097] In the example illustrated in the figures, the final composite element EF is a hollow cylindrical monostrand, such as a tubular bar, with an outside diameter, for example, between 5mm and 50mm, preferably between 10 and 20mm, comprising multifilament fibers embedded in a polymerizable material, such as a thermosetting sand resin.

[0098] The elementary filaments each have, for example, an average diameter between 5pm and 30qm.

[0099] As illustrated in [Fig.2], the manufacturing installation 100 comprises, in the direction of advancement of the multifilament fiber bundle along arrow F:

[0100] - a power supply device 111 comprising here several coils 112 supplying elementary filaments Fi_0 to form a multifilament fiber bundle E0,

[0101] - a vacuum chamber 113 or degassing chamber disposed between an inlet nozzle 113a and a separation nozzle 113b;

[0102] - an impregnation chamber 114 downstream of a vacuum chamber 113 and in particular of the separation nozzle 113b and filled with an impregnation composition 115 based of a polymerizable material and arranged upstream of an outlet nozzle so as to obtain at least two monostrands or a bundle of El fibers impregnated with polymerizable material;

[0103] - a 120 device for shaping the bundle of impregnated El fibers configured to produce an impregnated tubular bar E2 from the bundle of impregnated El fibers;

[0104] - a first radiation device 117 through which the tubular bar passes impregnated E2 and configured to perform partial or intermediate polymerization to form a pre-polymerized tubular bar E3;

[0105] - optionally, a guide device 130 for the tubular bar E3 pre- polymerized arranged downstream of the first radiation device 117 and configured to form a deformed tubular bar E4 and in particular, depending on the variant chosen, to guide the tubular bar to ensure good concentricity of the inner surface with respect to the outer surface or to deform the tubular bar in order to improve the outer surface of said bar while guiding it;

[0106] - a second radiation device 118 or final radiation device, distinct from the first radiation device 117, through which the deformed tubular bar E4 or the pre-polymerized tubular bar E3 passes when there is no guiding device 130 and configured to carry out a final polymerization to form the final composite element EF; and

[0107] - a translational drive device D along arrow F configured for to move the multifilament fiber bundle in translation to successively achieve degassing, impregnation of its fibers with polymerizable material and polymerization of the material as the bundle moves.

[0108] The vacuum chamber 113, the impregnation chamber 114, the shaping device 120, the first radiation device 117 and the second radiation device 118 are arranged along the same axis corresponding to the longitudinal axis of the installation 100 in the longitudinal direction X.

[0109] Generally, the fibers are delivered by one or more reels 112, called "rovings" in Anglo-Saxon terms. The bundle, coming from the feed device 111, crosses the installation advancing in the direction of arrow F, being set in motion by the drive device D located at the output of the device.

[0110] The translational drive device D is, for example, of the type comprising a motorized traction drum for winding the composite element around its axis or comprising two opposing motorized bands facing each other, which press with a certain force on the final composite element EF, to drive it by friction, in a translational movement, by passing it through the space between the two strips. Alternatively, any drive device could be used to move the multifilament fiber bundle in a direction of advancement.

[0111] The vacuum chamber 113 is, in a manner known per se, delimited by a rigid inlet nozzle 113a, provided with at least two through orifices and a rigid separation nozzle 113b, also provided with at least two through orifices located axially opposite the orifices of the inlet nozzle 113a.

[0112] The multifilament fiber bundle E0 is introduced into the vacuum chamber 113 by passing it through the orifices of the inlet nozzle 113a and exiting through the orifices of the separation nozzle 113b.

[0113] The vacuum chamber 113 is connected to a vacuum pump (not shown) which maintains a pressure level of approximately 0.1 bar in the vacuum chamber 113, despite the passage of multifilament fiber bundles E0 through orifices having a cross-section (total) greater than that of the multifilament fiber bundle E0 which passes through them.

[0114] The vacuum chamber 113 allows the multifilament fiber bundle E0 to be degassed by the action of the vacuum and thus to enhance the effectiveness of the subsequent impregnation and above all to guarantee the absence of bubbles inside the final composite element EF.

[0115] After passing through the vacuum chamber 113, the multifilament fiber bundle E0 enters an impregnation chamber 114 which is totally full of polymerizable impregnation material, therefore devoid of air.

[0116] The impregnation chamber 114 is a closed and sealed enclosure to prevent air from entering and resin from escaping.

[0117] The impregnation chamber 114 is delimited by the separation nozzle 113b and a rigid calibration nozzle, also provided with at least two through orifices located axially opposite the orifices of the separation nozzle 113b.

[0118] The impregnation chamber 114 is supplied with polymerizable material 115 from an external reservoir (not shown) via an inlet pipe 115a, here located in the upper part of said impregnation chamber 114.

[0119] The impregnation chamber 114 may also include, for example on its lower part, a drain pipe (not shown) for the polymerizable material.

[0120] The impregnation chamber 114 is totally filled with polymerizable material so that the bundle of multifilament fibers exiting the vacuum chamber 113 and which passes through it in a linear path is completely impregnated with polymerizable material.

[0121] The impregnation chamber 114 is, here, associated with a heating device 114b configured to heat the polymerizable material to a temperature between 50°C and 95°C, preferably between 60°C and 80°C.

[0122] Thus, the impregnated multifilament fiber bundle exits the impregnation chamber 114 at a temperature between 50°C and 95°C, preferably between 60°C and 80°C, before passing through the radiation devices 117, 118.

[0123] Alternatively, such a heating device 114b could not be provided.

[0124] The multifilament fiber bundle exiting the impregnation chamber 114 passes through an outlet nozzle 116 to form at least two monostrands or a bundle of impregnated multifilament fibers El. It could be envisaged that the multifilament fiber bundle exiting the impregnation chamber 114 remains in the form of a multifilament fiber bundle before entering the shaping device 120.

[0125] Generally, the shaping device 120 receives as input multifilament fibers El in the form of a bundle or at least two single strands exiting the impregnation chamber 114.

[0126] The shaping device 120, visible in detail in figures 3, 4 and 4A, comprises an external part 121 and an internal part 122 coaxial.

[0127] The internal part 122 extends inside the external part 121 over an axial length greater than the axial length of the external part 121. In other words, the internal part 122 extends axially beyond the lateral ends 121a, 121b of the external part 121.

[0128] As illustrated in the example of Figures 3, 4 and 4A, the inner part 122 and the outer part 121 are preferably independent of each other and mechanically connected to each other by radial fins 126, here two in number...

[0129] The external part 121 is delimited axially by two lateral ends 121a, 121b and radially by an external surface 121c and an internal surface 121d.

[0130] The upstream lateral end 121a has an outside diameter greater than the outside diameter of the downstream lateral end 121b and an inside diameter greater than the inside diameter of the downstream lateral end 121b, so that the internal surface 121d of the external part 122 has a slope 121e inclined from the upstream lateral end 121a to the downstream lateral end 121b over at least 10% of the total length of the external part 121.

[0131] Alternatively, it could be provided that the internal surface of the external part does not have such an inclined slope, but that the entrance of the external part can have a radius, variable or fixed.

[0132] Thus, the conical shape or with an entry radius of the upstream lateral end 121a allows the impregnated multifilament fibers El to insert more easily inside the external part 121.

[0133] The internal part 122 is a hollow tube radially delimited by an external surface 122a and an internal surface 122b.

[0134] The external surface 122a delimits with the internal surface 12Id of the external part 121 an external conduit 124.

[0135] The internal surface 122b delimits an internal conduit 125.

[0136] The shaping device 120 can be made of resin, for example by three-dimensional printing techniques, or in metallic material, for example in steel, for example by machining or three-dimensional printing techniques.

[0137] The impregnated multifilament fibers El pass through the external conduit 124 to form an impregnated tubular bar E2.

[0138] The outer part 121 is configured to form the outer diameter of the impregnated tubular bar E2 and the inner part 122 is configured to form the inner diameter of the impregnated tubular bar E2.

[0139] The internal conduit 125 allows air or nitrogen to circulate inside the impregnated tubular bar E2.

[0140] The internal part 122 has a length between 5cm and 1m.

[0141] The internal part 122 extends here along the entire length of the first device at radiation 17.

[0142] Generally, the inner part 122 extends at least partly inside the first radiating device 117, so that when the impregnated tubular bar E2 exits the outer part 121 of the shaping device 120, said impregnated tubular bar E2 remains guided by the inner part 122.

[0143] The first radiation device 117 is configured to pre-polymerize, i.e. to perform a partial polymerization of the impregnated tubular bar E2 in order to stiffen said bar E2 so that it retains its shape while preventing it from sticking to the inner part 122. The resin in contact with the inner part 122 remains liquid, so that the friction forces between the inner part 122 and the bar E2 remain low, allowing a high production speed.

[0144] The first radiation device 117 includes a first light source 117a with ultraviolet radiation, acronym UV.

[0145] The exposure time of the impregnated tubular bar E2 to the first ultraviolet light source is between 0.1s and 1.5s, preferably between 0.4s and 0.7s.

[0146] The power of the first ultraviolet light source is between 0.5 kW and 14 kW, preferably between 1 kW and 5 kW.

[0147] For example, the first light source comprises a plurality of light-emitting diodes (not shown), acronym LED, preferably directed radially towards the impregnated tubular bar E2.

[0148] For example, the power of LEDs is between 0.5kW and 14 kW, preferably between 1 kW and 5 kW.

[0149] For example, the first light source with radiation is configured to emit only ultraviolet, monochromatic radiation, for example via LEDs, the available wavelengths of which are: 365, 385, 395, 405nm, and more generally between 200nm and 405nm.

[0150] The first 117a ultraviolet light source with LEDs therefore makes it possible to emit radial radiation on the impregnated tubular bar El, with or without reflectors to optimize irradiation.

[0151] According to yet another variant, the first light source 117a could comprise a plurality of mercury vapor lamps configured to emit broad-spectrum ultraviolet UV radiation, infrared radiation and visible light.

[0152] The first radiation device 117 is configured to partially polymerize or pre-polymerize the impregnated tubular bar E2 and deliver a pre-polymerized impregnated tubular bar E3.

[0153] By "partial polymerization or pre-polymerization", it is understood that the degree of polymerization of the impregnated tubular bar E2 has reached between 35% and 65% of complete polymerization.

[0154] The pre-polymerization step makes it possible to obtain a pre-polymerized tubular bar E3, ideally non-sticky, capable of no longer deforming in the free state while being malleable, if necessary, to be deformed under mechanical stress.

[0155] The second radiation device 118 or final radiation device includes a second light source 118a with combined ultraviolet and infrared radiation or with infrared radiation alone configured to complete the polymerization of the pre-polymerized tubular bar E3.

[0156] Complete polymerization of the composite is obtained when the degree of polymerization of the polymerizable material is close to 100%, preferably greater than or equal to 95%.

[0157] The exposure time of the pre-polymerized tubular bar E3 to the second light source combining ultraviolet and infrared rays is between 1s and 6s, preferably between 1.5s and 3s.

[0158] The power of the second combined UV and infrared light source is between 6 kW and 60 kW, preferably between 20 kW and 40 kW.

[0159] According to one embodiment, the second light source comprises a plurality of light-emitting diodes (not shown), acronym LEDs, preferably directed radially towards the pre-polymerized tubular bar E3, whose wavelengths Available wavelengths are between 200nm and 405nm, preferably between 365nm and 405nm.

[0160] According to another variant, the second light source 118a could comprise a plurality of mercury vapor lamps, wherein the exposure time of the pre-polymerized tubular bar E3 is between 1 s and 4 s, preferably between 1.5 s and 2 s, at a power between 6 kW and 60 kW, preferably between 20 kW and 40 kW.

[0161] According to one variant, the second light source 118a could comprise a plurality of mercury vapor lamps configured to emit broad-spectrum ultraviolet UV radiation, infrared radiation and visible light and a plurality of lamps with infrared radiation wavelengths between Ipm and 3pm.

[0162] According to yet another variant, the second light source could be an infrared-only light source. In this case, the second radiating device comprises an infrared-only light source configured to emit only infrared radiation with a wavelength between 1pm and 3pm.

[0163] In this case, the exposure time of the pre-polymerized tubular bar E3 to the second light source combining infrared radiation alone is between 2s and 8s, preferably between 3s and 4s and the power of this second infrared light source is between 10kW and 60kW, preferably between 20kW and 40kW.

[0164] Alternatively, a third radiation device with an infrared light source could be provided downstream of the second radiation device.

[0165] As illustrated, and in no way limiting, the installation 100 includes a guide device 130 for the pre-polymerized tubular bar E3 located between the first radiating device 117 and the second radiating device 118. Alternatively, the installation 100 could be provided without such a guide device.

[0166] The guide device 130 of the pre-polymerized tubular bar E3 is configured to support the pre-polymerized tubular bar E3 and consequently the impregnated fibers El in order to ensure that the internal part 122 of the shaping device 120 is located in the center of said impregnated fibers El and / or to improve, by deformation, the circular shape of the section of the pre-polymerized tubular bar E3 and obtain a deformed tubular bar E4.

[0167] As illustrated, the guide device for the pre-polymerized tubular bar E3 comprises a fixed structure (not visible) and two guide elements or rollers 131, 132 attached to said fixed structure.

[0168] Each roller 131, 132 is mobile in rotation around an axis of rotation fixed to said fixed structure.

[0169] The axes of rotation extend along a transverse axis Y perpendicular to the longitudinal axis of advancement X.

[0170] The two rollers 131, 132 are fixed in translation along the vertical axis Z.

[0171] The two rollers 131, 132 are aligned on a vertical axis ZI parallel to the vertical axis Z and are opposite in the vertical direction with respect to the pre-polymerized tubular bar E3 which passes between said rollers 131, 132.

[0172] As illustrated, the guidance device 130 comprises a set of two rollers 131, 132 superimposed vertically. Alternatively, a plurality of sets of two rollers arranged in series along the direction of advance X of the beam could be provided.

[0173] In the case where the installation 100 includes such a guiding device 130, the deformed tubular bar E4 enters the second radiating device 118.

[0174] The embodiment illustrated in Figures 5 and 5A, in which the same elements bear the same references, differs from the embodiment illustrated in Figures 3, 4 and 4A only in that the internal part 122 and the external part 121 of the shaping device 120 are independent of each other and are not mechanically connected to each other.

[0175] In this embodiment, the shaping device 120 includes a fixing support 140 for the internal part 122 arranged upstream of the external part 121. Thus, the impregnated fibers El do not touch the fixing support 140. This allows better flow inside the external part 122. In this embodiment, the internal part 122 and external part 121 are also simple to manufacture.

[0176] The mounting support 140 here comprises two mounting fins 140a, 140b radially opposed with respect to the longitudinal axis of the installation 100 connected by a central tubular part 140c in which the internal part 122 is mounted.

[0177] The fixing fins 140a, 140b are fixed to the housing of the installation 100.

[0178] Alternatively, a different number of fixing fins could be provided.

[0179] In this embodiment, the internal surface of the external part 122 does not have an inclined slope forming a cone, but the entrance of said external part 122 has a radius, here variable.

[0180] In this embodiment, the radiating devices 117, 118 are identical to those described with reference to the previous embodiment. The description will not be repeated here.

[0181] The installation according to the invention makes it possible to produce continuously a tubular composite bar with a circular cross-section and not requiring post-treatment.

[0182] Such an installation can easily be implemented on all existing composite reinforcement production lines.

[0183] Thanks to the mechanical deformation device, it is possible to give a circular shape to the composite bar before final polymerization.

[0184] The shaping device 120 according to the invention is easily installed on a production line for tubular composite bars with a circular cross-section, before the first UV lamp.

Claims

1. Demands Installation (100) for the continuous manufacturing of a long, thin composite element (FE) comprising a bundle of multifilament fibers impregnated with a composition based on a polymerizable material, the installation (100) comprising, in the direction of advancement (X) of the bundle of multifilament fibers: - a power supply device (111) configured to form a multifilament fiber bundle (E0); - a degassing chamber (113) for the multifilament fiber bundle (E0); - an impregnation chamber (114) filled with a composition based on a polymerizable material and configured to impregnate said degassed multifilament fiber bundle (E0) with said composition and form impregnated multifilament fibers (El), said impregnation chamber (114) being located downstream of the degassing chamber in the direction of advancement of the multifilament fiber bundle; - a device (120) for shaping impregnated multifilament fibers (El) configured to produce an impregnated tubular bar (E2) of polymerizable material from the impregnated multifilament fibers (El); - a first radiation device (117) through which the impregnated tubular bar (E2) passes and configured to perform a partial polymerization of said impregnated tubular bar (E2) and to form a pre-polymerized tubular bar (E3); and at least - a second radiation device (118), separate and distinct from the first radiation device (117) configured to form a final composite element (EF), and - a translational drive device (D) configured to drive the multifilament fiber bundle in translation and to apply a tension to said multifilament fiber bundle, characterized in that the shaping device (120) comprises an external part (121) configured to form the outer diameter of the impregnated tubular bar (E2) and an internal part (122) configured to form the inner diameter of the impregnated tubular bar (E2), the internal (122) and external (121) parts being coaxial and defining a conduit between them external (124) configured to receive the impregnated multifilament fibers (El), the internal part (122) extending at least partly inside the first radiating device (117).

2. Installation (100) according to claim 1, wherein the external part (121) of the shaping device (120) is delimited axially by two lateral ends (121a, 121b) and radially by an external surface (121c) and an internal surface (121d), and wherein the internal part (122) of the shaping device (120) extends inside the external part (121) over an axial length greater than the axial length of the external part (121).

3. Installation (100) according to claim 2, wherein the upstream lateral end (121a) of the external part (121) of the shaping device (120) has an outside diameter greater than the outside diameter of the downstream lateral end (121b) and an inside diameter greater than the inside diameter of the downstream lateral end (121b).

4. Installation (100) according to any one of the preceding claims, wherein the internal part (122) of the shaping device (120) is a hollow tube radially delimited by an external surface (122a) and an internal surface (122b), the external surface (122a) delimiting with an internal surface (121d) of the external part (121) the external conduit (124) for receiving the impregnated multifilament fibers (El).

5. Installation (100) according to claim 4, wherein the internal surface (122b) of the internal part (122) of the shaping device (120) delimits an internal conduit (125).

6. Installation (100) according to any one of the preceding claims, wherein the internal part (122) and the external part (121) of the shaping device (120) are independent of each other and mechanically connected to each other.

7. Installation (100) according to any one of claims 1 to 5, wherein the internal part (122) and the external part (121) of the shaping device (120) are independent of each other and are not mechanically connected to each other.

8. Installation (100) according to claim 7, wherein the shaping device (120) includes a fixing support (140) for the inner part (122) disposed upstream of the outer part (121).

9. Installation (100) according to any one of the preceding claims, comprising a bar guiding device (130) tubular (E3) pre-polymerized disposed between the first radiation device (117) and the second radiation device (118) in the direction of advancement of the multifilament fiber bundle.

10. Installation (100) according to claim 9, wherein the pre-polymerized tubular bar (E3) guide device (130) is configured to plastically deform the pre-polymerized tubular bar (E3) and to form a deformed tubular bar (E4), said guide device (130) comprising: - at least one set of two shaping members (131, 133), located one above the other in a direction perpendicular to the direction of advancement of the multifilament fiber bundle, on either side of the pre-polymerized tubular bar (E3), the two shaping members (131, 132) being rotationally movable each about a transverse axis of rotation.

11. Installation (100) according to any one of the preceding claims, wherein the first radiating device (117) comprises a first ultraviolet light source (117a).

12. Installation (100) according to claim 11, wherein the first light source (117a) comprises a plurality of light-emitting diodes configured to emit monochromatic ultraviolet radiation with a wavelength between 200nm and 405nm.

13. Installation (100) according to claims 11 or 12, wherein the first ultraviolet light source (117a) further comprises infrared radiation.

14. Installation (100) according to claim 11, wherein the first ultraviolet light source (117a) comprises a plurality of mercury vapor lamps configured to emit broad-spectrum ultraviolet radiation, infrared radiation and visible light.

15. Installation (100) according to any one of the preceding claims, wherein the second radiation device (118) comprises a second light source (118a) with combined ultraviolet and infrared radiation or with infrared radiation alone to complete the polymerization of the pre-polymerized tubular bar (E3, E4).

Citation Information

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