WO2022073862A1

WO2022073862A1 - Curing apparatus for coatings of glass fibers

Info

Publication number: WO2022073862A1
Application number: PCT/EP2021/077073
Authority: WO
Inventors: Samir Lamrini
Original assignee: Samir Lamrini
Priority date: 2020-10-05
Filing date: 2021-10-01
Publication date: 2022-04-14
Also published as: EP4225713A1; DE102020126039A1

Abstract

The present invention relates to a curing apparatus (1, 2) for coatings of glass fibers (4) having a receiving space (11, 21) suitable for a coated glass fiber (4) to be passed through in a direction of motion (A), wherein the receiving space (11, 21) comprises a plurality of UV radiation sources (12, 22) which are configured for curing the coating of the glass fiber (4) by means of UV light. The curing apparatus (1, 2) is characterized in that the receiving space (11, 21) comprises at least one protective gas opening (14c, 24c) configured for allowing a protective gas to flow into the receiving space (11, 21), preferably through delivery by the curing apparatus (1, 2), and the receiving space (11, 21) comprises at least one protective gas opening (14c, 24c) configured for allowing the protective gas to escape from the receiving space (11, 21), preferably through suctioning by the curing apparatus (1, 2).

Description

DESCRIPTION

Curing device for coatings of glass fibers

The present invention relates to a curing device for coatings of glass fibers according to the preamble of patent claim 1.

Glass fibers are nowadays used in many different technical fields. One of the highly technical applications is the transmission of light using glass fibers. This can be used for data transmission using light, so that the glass fibers can also be referred to as optical waveguides. Glass fibers are also used in medicine, for example for lighting and for generating images, for example in microscopes, in inspection cameras and in endoscopes. Furthermore, glass fibers can be used in sensors, which can then be referred to as fiber-optic sensors.

Another area of application for glass fibers is laser technology. Here, the laser radiation can be guided as signal light radiation by means of a passive glass fiber from a laser radiation source as a signal light radiation source to a processing point in order to carry out cutting or welding there, for example in material processing or in medicine . In this way, the laser beam can also be supplied as laser radiation to a sample, for example in metrology, in microscopy or in spectroscopy, for example. Such applications are known, for example, in mechanical engineering, in telecommunications, in medical technology and in sensor technology. Glass fibers can also be used to generate or amplify laser light and are then referred to as active glass fibers.

Glass fibers are usually drawn as a blank as thin threads from a glass melt, so that a glass fiber is a long, thin fiber made of glass. The blank can also be referred to as a preform. The preform is usually produced in a preceding work step, usually as a glass rod typically about 1 m in length and about 10 mm to about 50 mm in diameter, which already has the refractive index profile of the subsequent glass fiber. The glass fiber is then drawn from the preform by melting it, which can be done in a fiber drawing tower at temperatures of around 2000°C, to which the preform is heated for this purpose. At this temperature, the glass material of the preform becomes sufficiently soft so that the glass material of the preform becomes a glass fiber. water can be drawn, which has a significantly smaller diameter with a correspondingly greater length than the preform. The refractive index profile of the preform is usually preserved during the drawing process. The speed at which the glass fiber is pulled out of the preform can be regulated as a function of the diameter of the glass fiber, which can be detected by sensors for this purpose. Pulling the glass fiber out of the preform leads to the formation of a bare glass fiber from the material of the preform, which can be referred to as the glass fiber core, or fiber core for short.

Usually, immediately after drawing, the glass fiber core is provided or covered with a coating of plastic such as polyamide, acrylic or silicone in a further process step in the same manufacturing process, which usually serves to mechanically protect the glass fiber core but also specifically to influence the optical properties of the Glass fiber can be used. For this purpose, the glass fiber core of the glass fiber is guided through an extruder, which provides the plastic in a free-flowing form and applies it to the outer surface of the glass fiber core. In an immediately subsequent process step, the plastic on the outer surface of the glass fiber core is etched by irradiating it with light in the ultraviolet spectrum (UV light), i.e. with electromagnetic radiation in the optical frequency range (light) with shorter wavelengths than the light visible to humans, which occurs in the range between about 100 nm and about 405 nm are cured for coating. The coating can also be referred to as a glass fiber cladding, which is closed in the circumferential direction and thus completely surrounds the glass fiber core, apart from the two open ends of the glass fiber or glass fiber core.

Thus, when curing the coating which has just been applied to the fiberglass core moving in a longitudinal direction as the pulling direction, the coated fiberglass core is passed through a curing device which can generate UV light and direct it onto the coated fiberglass core moving in the longitudinal direction. The glass fiber core enters the curing device with a freshly applied coating and exits with a cured coating in the longitudinal direction opposite. The generation of the UV light and/or the alignment of the UV light onto the coated glass fiber core can take place in different ways.

US 4,710,638 A describes an apparatus for treating material with radiant energy, particularly suitable for curing photocurable polymeric materials coated on an optical fiber. The device includes first and second reflectors which in combination form an elliptical reflector, a light source arranged parallel to the optical fiber and positioned at a focal point of the elliptical reflector, and a photocurable polymer coated wire-like material or fiber such as an optical fiber in the second focal point is positioned. An auxiliary reflector is located near the second focus in a position to direct light rays impinging thereon to the second focus, thereby increasing the amount of energy impinging on the polymeric coating.

US Pat. No. 6,419,749 B1 describes a tubular device for UV curing of coatings on a continuous filament, in which concentric tubes are provided and through which the filament passes after coating to cure the coating, the device having the first inner tube carrying the UV directs light through the tube to cure the filament passing therethrough, and has a second concentric tube, located over and spaced from the first tube, that reflects IR light and transmits UV light to prevent burning and destruction of the to prevent coating on the filament as it passes through the first tube. The UV light source is tubular and arranged parallel to the continuous filament.

US Pat. No. 9,132,448 B2 describes devices and methods for curing materials with radiant energy. The devices include a first reflector and a second reflector which are semi-ellipses. The ellipses that define the first reflector and the second reflector have axes of different lengths, and the reflectors are aligned such that the focal points of the reflectors overlap. A source of radiant energy at a near focus of a reflector can provide energy to cure a coating on a substrate at a far focus of the reflector. The different sizes of the two reflectors reduce the focussing error of the radiant energy and provide improved efficiency of the curing system. The radiant energy source is tubular and arranged parallel to the substrate.

The devices and/or methods described above have in common that a tubular UV light source is used in each case, which extends in the same longitudinal direction as the moving coated glass fiber core and parallel to the glass fiber core. The UV light from the tubular UV light source is reflected and focused towards the moving coated glass fiber core by means of elliptically shaped shields. Accordingly, the moving coated glass fiber core must be located exactly in the focal point of the reflected UV light so that its coating can be cured. If this is not the case, the coating can be cured incompletely, unevenly or even not at all. Fluorescent lamps, for example, can be used as a tubular UV light source, which can be implemented as low-pressure gas discharge tubes with mercury vapor as the gas filling. However, iron iodide lamps, gallium iodide lamps and amalgam lamps are also known.

However, the disadvantage of generating UV light or UV irradiation using UV fluorescent tubes is that UV fluorescent tubes can generate and emit a comparatively broad spectrum of UV light, but usually only a small range of the emitted spectrum of the UV Light helps to cure the coating on the fiber optic core. Approx. 90% of the energy generated is lost heat, which excessively heats up the material of the coating and/or the glass fiber core and can damage it as a result. If the material of the coating of the glass fiber core is heated or heated too much, the viscosity of the coating can drop sharply, for example from a temperature of approx mechanical properties of the material of the coating of the glass fiber core can be changed. Additionally or alternatively, this can affect the light-guiding properties of the coating of the glass fiber. If, alternatively or additionally, the material of the glass fiber core is warmed up or heated too much, the material can become softer and thus flow more when it is pulled, as a result of which the cross section of the glass fiber core can narrow. This can affect the optical properties of the glass fiber core and/or reduce the mechanical strength of the glass fiber core.

Another disadvantage here is that the heat loss from the UV fluorescent tubes can also lead to high heating of the curing device itself and can also stress it as a result.

Another disadvantage of generating UV light or UV irradiation using UV fluorescent tubes is that UV fluorescent tubes require a comparatively high electrical output during operation, which can amount to several kilowatts (kW). This can lead to a very low efficiency of the conversion of electrical energy into UV radiation and thus to a very low efficiency of the curing process of the curing device. The corresponding need for electrical energy can lead to correspondingly high costs, which can increase the production costs of the glass fiber.

Another disadvantage of generating UV light or UV radiation using UV fluorescent tubes is that the power or the intensity of the UV radiation in UV fluorescent tubes such as low-pressure mercury vapor lamps is structurally fixed and on the known movement or drawing speed of the glass fiber must be matched in order to achieve the desired curing of the coating and at the same time not to stress or damage the material of the coating of the glass fiber core and/or the material of the glass fiber core itself by excessively strong UV radiation . This can also have a negative effect on the properties and in particular on the durability of the material of the coating of the glass fiber core and/or the material of the glass fiber core, as already described above.

US 8,604,448 B2 describes a method for curing a coating on an optical fiber comprising: emitting UV radiation from one or more sources in the form of a UV LED or multiple UV LEDs of electromagnetic radiation into a substantially cylindrical cavity with an elliptical cross section wherein the cavity has a reflective inner surface, defines the cure space, and defines a first line focus and a second line focus; culverts part of the emitted UV radiation completely through the curing space; reflecting at least a portion of the UV radiation toward the second line focus by the reflective inner surface; and passing an optical fiber with an incompletely cured coating through the curing space along the second line focus to cause absorption of both emitted and reflected UV radiation.

EP 2 388 239 B1 describes an apparatus for curing a coated glass fiber, comprising: a substantially cylindrical cavity having a substantially elliptical cross section and a reflective inner surface, the cavity defining a first line focus, a second line focus and a major axis defining the intersects the first line focus and the second line focus, the second line focus defining a cure axis; a protective tube that is substantially transparent to UV radiation, the protective tube surrounding the cure axis and preferably being a quartz tube; and a UV LED source positioned within the cavity at the first line focus, the UV LED source having an emission pattern that defines a line of average emission and an emission angle between the major axis and between about 30 degrees and 100 degrees having.

LEDs are generally characterized by a comparatively long service life, by a comparatively high energy efficiency in the conversion of electrical energy into optical radiation, by a comparatively low consumption of electrical energy, by comparatively low costs, by a comparatively small installation space and/or by a comparatively small warming up. Thus, the disadvantages of UV fluorescent tubes described above can be at least partially reduced or avoided by using UV LEDs as UV light sources instead.

However, all the previously described curing devices using UV radiation still have the disadvantage that it is always necessary to align the UV light by reflecting and focusing it on the coated glass fiber core in order to bring about the desired curing. This applies both to the generation of UV light using UV fluorescent tubes and using UV LEDs as UV light sources. For this purpose, either flat, in particular elliptical, reflectors or lenses can be used. In any case, this focuses the UV light in the plane perpendicular to the pulling or moving or longitudinal direction of the glass fiber onto a curing axis, which extends in the longitudinal direction and can be referred to as the focal point or line focus as described above.

Conversely, however, this means that the coating of the glass fiber core can only be cured effectively and as completely as possible using UV light if the coated glass fiber core lies as exactly as possible with its longitudinal axis on the line focus or in the focal point of the reflectors. This must be done accordingly over the entire length with which the coated glass fiber core runs through the curing device. In other words, the longitudinal or pulling axis of the glass fiber and the line focus of the curing device or the focal point over the entire length of the curing device.

This requires a correspondingly exact adjustment of the curing device in relation to the fiber drawing tower. The sensitivity of this adjustment is in the order of microns compared to the fiber drawing tower, whose dimensions are usually more in the order of meters. As a result, even a slight misalignment of the line focus of the curing device in relation to the longitudinal or pulling axis of the glass fiber means that the glass fiber or the coated glass fiber core is not or only partially irradiated by UV light and the coating is only insufficiently cured as a result can be.

The problem here is that an uneven or insufficiently cured coating of the glass fiber core can usually only be recognized as a manufacturing defect when a large proportion of the glass fiber has already gone through the process step of curing and has subsequently been wound up. This leads to a correspondingly high level of rejects in production.

With such curing devices, for example from EP 2 388 239 B1, as already mentioned, it is also known to arrange a protective tube within the curing device in such a way that the coated glass fiber core can be pulled through the protective tube in its direction of movement, movement or longitudinal direction the longitudinal direction of which can be pulled through without touching the protective tube radially, and in this case is guided in particular centrally or coaxially with the protective tube. This protects the UV radiation sources and the coated glass fiber core from mutual contact. Such a protective tube can in particular be made of quartz glass, since quartz glass has a very high transparency for UV light and thus the UV light directed onto the coated glass fiber core can largely reach the coating of the glass fiber.

The protective tube can also be used to allow a protective gas, such as nitrogen, to flow into the interior of the protective tube from one end and exit through the opposite end from the interior of the protective tube, see also EP 2 388 239 Bl The coating of the glass fiber takes place in an oxygen-free or low-oxygen environment, which can avoid or reduce errors during the curing of the coating of the glass fiber.

One object of the present invention is to provide a curing device for coatings of glass fibers of the type described at the beginning, so that the possibilities for curing the coating of a glass fiber core of a glass fiber to be produced can be improved. In particular, the degree of curing and thus the quality of the curing of the coating of the glass fiber should be improved. Additionally or alternatively, the expense of curing the coating of the glass fiber should be kept as low as possible. Additionally or alternatively, the effort involved in adjusting the coated glass fiber core to be cured in relation to the curing device can be reduced or avoided. At the very least, an alternative to known curing devices of this type for coating glass fibers should be created.

The object is achieved according to the invention by a curing device for coatings of glass fibers with the features of claim 1. Advantageous developments are described in the dependent claims.

The present invention thus relates to a curing device for coatings of glass fibers with a receiving space for guiding a coated glass fiber through in a direction of movement, the receiving space having a plurality of UV radiation sources which are designed to cure the coating of the glass fibers using UV light. Such curing devices are used to irradiate a glass fiber during production when pulling it out of the preform and then applying a coating, for example by means of an extruder, in a further process step with UV light of a suitable wavelength and to a sufficient extent, so that the material of the coating like for example polyamide, acrylic or silicone can be cured sufficiently. Known curing devices of this type have been described in the introduction. The direction of movement of the coated glass fiber usually corresponds to the vertical direction when the curing device is used as intended, which can also be referred to as the longitudinal direction or pulling direction of the coated glass fiber.

The curing device according to the invention is characterized in that the receiving space has at least one protective gas opening which is designed to allow a protective gas to flow into the receiving space, preferably by conveying the curing device, and the receiving space has at least one protective gas opening which is designed to allow the protective gas preferably by suction of the curing device to escape from the receiving space. Such a protective gas is used at least to remove or reduce oxygen in the vicinity of the coating during the curing process using UV light. Nitrogen, for example, can be used as such a protective gas.

Here, it has hitherto been known to let the protective gas flow into the receiving space from the lower end of the receiving space of such known curing devices and to let it exit again at the upper end of the receiving space in the vertical direction, or vice versa. However, this can lead to an uneven distribution of the shielding gas along the coated glass fiber. If a gas is used which interacts with the coating during its UV curing, the gas may be partially consumed over the distance from one end of the cavity to the other end of the cavity, which may impair performance. According to the invention, therefore, at least one protective gas opening is provided, through which the protective gas can flow into the receiving space. This protective gas opening can be referred to as a protective gas opening for inflow or, for short, as a protective gas inlet. The inert gas can flow in by opening a source of inert gas such as a gas cylinder and the pressure of the inert gas inside the gas cylinder leading to a flow of inert gas which is conducted via the inert gas opening to flow into the receiving space. Preferably, the flow of the protective gas can be generated by means of a conveyor, such as a pump of the curing device, or by means of an external conveyor, such as an external pump, which can lead to a constant flow of the protective gas with regard to the flow rate, which can preferably be selected in a targeted manner can.

According to the invention, at least one protective gas opening is also provided, through which the protective gas can escape from the receiving space. This inert gas opening can be referred to as inert gas vent for escape or in short as inert gas outlets. The shielding gas can be escaped by the shielding gas being pushed by the flow of the inflowing or post-flowing shielding gas from the inlet opening to the outlet opening and into it, which can keep the shielding gas escaping easy. Preferably, the protective gas can be actively sucked in or sucked into the protective gas opening to escape by means of a conveyor, such as a pump of the curing device or by means of an external conveyor, for example by means of an external pump, which can increase the escape and make it more constant.

The previously described effects can be achieved by using only one conveying means for conveying the protective gas into the receiving space or for sucking the protective gas out of the receiving space. At the same time, the effort for this can be kept comparatively low. If both conveying means are used in combination with one another, this can increase the effort accordingly, but the effects described above can also be achieved together, which improves the uniformity of the flow of protective gas through the receiving space or a flow of protective gas that remains constant over time can effect or promote through the receiving space.

In any case, the invention is based on the finding that the protective gas can be introduced into the receiving space through a protective gas opening and also discharged from it through a further protective gas opening on the part of the curing device, so that a comparatively even or constant flow of protective gas is achieved can be. As a result, the effect of the protective gas can be improved. It is particularly advantageous here that the protective gas opening for inflow and the protective gas opening for escaping are arranged within the receiving space and the use or guidance of the protective gas can therefore take place completely within the receiving space or can be restricted thereto. In particular, through the protective gas opening for escaping and in particular in the case of suction, it can be prevented that the protective gas can escape from the receiving space of the curing device into the environment at all.

It is advantageous at the protective gas opening for escaping and in particular during suction that vapors from the receiving space can escape or be suctioned off in a targeted manner, which vapors can arise when the coating of the glass fiber is cured. Such vapors can be harmful to human health, which is why it is desirable to reduce or even completely avoid the escape of such vapors from the receiving space into the environment. Correspondingly, these vapors can be held within the receiving space and from there can be discharged or sucked off in a targeted manner via the inert gas opening for escaping, without reaching the area surrounding the curing device.

Preferably, the interior surface of the receiving space can be designed to be reflective, at least in sections or completely, in order to be able to distribute the UV radiation as evenly as possible and/or to be able to use it as completely as possible. This can be achieved by means of a mirror coating.

According to one aspect of the invention, the protective gas opening for inflow and the protective gas opening for escaping are offset from one another in the direction of movement of the coated glass fiber. As a result, a certain distance can be created between the inert gas opening for inflow and the inert gas opening for escape, over which the inert gas can flow as described above. The offset of the protective gas opening for inflow and the protective gas opening for escaping can preferably be significantly greater along the direction of movement of the coated glass fiber than in the other spatial directions, so that the protective gas can flow over a correspondingly long distance as described above. If more than two protective gas openings are used for inflow and/or more than two protective gas openings for escape, these can preferably be arranged equidistantly along the direction of movement of the coated glass fiber, which can lead to a correspondingly uniform effect.

According to a further aspect of the invention, the receiving space has at least one protective gas opening, which is designed to allow the protective gas to flow into the receiving space, preferably by conveying the curing device, and the receiving space has at least two protective gas openings, which are designed to let the protective gas, preferably by suction of the curing device to escape from the receiving space, wherein the protective gas opening for inflow in the direction of movement of the coated glass fiber between the two protective gas openings for Escape, preferably centrally located. As a result, the protective gas can escape or be sucked off along the direction of movement of the coated glass fiber on both sides of the protective gas opening towards the inflow, so that a flow of the protective gas can be achieved as described above. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the receiving space has at least two protective gas openings which are designed to allow the protective gas to flow into the receiving space, preferably by conveying the curing device, and the receiving space has at least one protective gas opening which is designed to let the protective gas, preferably by sucking off the curing device, from the receiving space, wherein the protective gas opening for escaping is arranged in the direction of movement of the coated glass fiber between the two protective gas openings for inflow, preferably centrally. As a result, the properties and advantages described above can be implemented in a correspondingly reversed constellation of two inert gas openings for inflow and one inert gas opening for escape. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the protective gas opening for inflow and the protective gas opening for escape are arranged in the same plane perpendicular to the direction of movement of the coated glass fiber. Hereby a comparatively short distance of the flow of the shielding gas can be achieved by arranging the shielding gas inflow opening and the shielding gas exit opening within the same plane, which is perpendicular to the direction of movement of the coated glass fiber, so that an offset of the shielding gas inflow opening below the shielding gas exit opening along the direction of movement of the coated glass fiber is avoided. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the protective gas opening for inflow and the protective gas opening for escape are arranged diametrically opposite one another with respect to the direction of movement of the coated glass fiber. At the same time, it can be achieved or promoted that the flow of the protective gas passes as close as possible or directly to the coated glass fiber, preferably on both sides and particularly preferably evenly, which can promote the implementation of the properties and advantages described above. In this way too, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the receiving space has at least two protective gas openings which are designed to allow the protective gas to flow into the receiving space, preferably by conveying the curing device, and the receiving space has at least two protective gas openings, which are designed to allow the protective gas to escape from the receiving space, preferably by suction from the curing device, the protective gas openings for inflow and the protective gas opening for escaping in the same plane perpendicular to the direction of movement of the coated glass fiber being spaced alternately from one another, preferably evenly spaced, are arranged. In this way, in particular, the design options for the flow of the protective gas can be increased. In particular, a flow that is as uniform as possible can be achieved within the plane perpendicular to the direction of movement of the coated glass fiber.

According to a further aspect of the invention, the receiving space has at least two protective gas openings, which are designed to allow the protective gas to flow into the receiving space, preferably by conveying the curing device, the protective gas openings for flowing in being offset in the direction of movement of the coated glass fiber and arranged linearly in relation to one another , and/or the receiving space has at least two protective gas openings, which are designed to allow the protective gas to escape from the receiving space, preferably by suction from the curing device, the protective gas openings for escaping in the direction of movement of the coated glass fiber being arranged offset to one another in a linear manner. This can simplify the implementation or production of the respective inert gas openings. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the at least two protective gas openings for inflow are connected to a common protective gas line, the at least two protective gas openings for escape are connected to a common protective gas line and the curing device is designed to push the protective gas in opposite directions or in the same direction through the protective gas line of the protective gas openings to flow in and to escape through the shielding gas line of the shielding gas openings. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the protective gas opening for inflow and/or the protective gas opening for escaping are aligned perpendicularly to the direction of movement of the coated glass fiber. In other words, it can hereby be achieved that the protective gas can flow through the protective gas opening for inflow, directed radially onto the coated glass fiber, into the receiving space. Correspondingly, in addition or as an alternative, the protective gas can be discharged again radially from the receiving space through the protective gas opening in order to escape. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the receiving space has at least one temperature sensor, which is designed to detect a temperature of the protective gas, and the curing process direction is designed to temper the inflowing protective gas depending on the detected temperature of the protective gas in the receiving space. Such a temperature measurement or temperature detection of the temperature sensor can take place, for example, via a temperature-dependent electrical resistance.

In any case, in this way the curing device or a control unit of the curing device can be provided with information about the current temperature of the protective gas, which represents the gas inside the receiving space, in the region of the temperature sensor. Depending on this detected temperature, the temperature of the protective gas can be controlled by means of regulation in such a way that it corresponds to a predetermined temperature when the temperature sensor is reached. Depending on the predetermined temperature, tempering can lead to a reduction in the temperature of the protective gas as cooling or to an increase in the temperature of the protective gas as heating. The curing device can do this, for example, by means of a heat pump, by means of electrical heating or the like. As a result, the protective gas can have the predetermined temperature within the receiving space.

This aspect of the present invention is based on the knowledge that the temperature of the protective gas can be used to influence the reaction speed or the polymerization speed of the coating of the glass fiber and in particular can be increased by an increased temperature. The latter can enable the glass fiber to be drawn from the preform at a higher speed than previously known, which means that the production speed can be increased. This can accelerate and thus increase the production of the glass fiber, which can reduce the cost of the glass fiber.

According to a further aspect of the invention, the accommodation space is designed to accommodate the protective gas and the coated glass fiber in direct contact with one another. The coated glass fiber can thus come into direct contact with the protective gas, which can flow in via the protective gas opening to flow into the receiving space. In other words, a protective tube or a quartz tube as known, for example, from EP 2 388 239 B1 is dispensed with. This can reduce the complexity of the curing device, since a protective tube can be dispensed with as a component. In particular, the properties and advantages described above can be achieved, which are based on direct contact of the protective gas with the coating of the glass fiber.

This aspect of the invention is also based on the knowledge that, as described above, such a protective tube, in particular made of quartz glass, has a very high transparency for UV light and thus the UV light directed onto the coated glass fiber core largely reaches the coating of the glass fiber can let. Nevertheless, Fresnel losses of approx. 7% per interface can occur at the air-to-glass interface, so that this proportion of the primary radiation losses do not reach the coating of the glass fiber inside the protective tube or quartz tube, but can be reflected back on the outer wall of the protective tube or quartz tube.

Up to now, the opacity, i.e. the absorption losses, of the quartz glass itself, which occurs in quartz tubes of this type, has also had to be taken into account. Quartz tubes of this type usually have a thickness of at least approx. 2 mm and the UV light of the primary radiation is usually weakened again in this section.

Furthermore, such protective tubes or quartz tubes are usually round and thus represent a curvature for the incident and partially passing UV light of the primary radiation. Consequently, imaging errors can occur here, which can only be compensated for with great effort, if at all.

These effects can individually and especially in combination with each other reduce the effect of the UV light of the primary radiation on the coating of the glass fiber, which can lead to a corresponding loss of quality in curing or to a correspondingly more powerful and/or longer-lasting irradiation in order to achieve the desired result to obtain. This can increase the complexity of the manufacturing process and thus also the cost of the coated glass fiber.

If a protective tube or quartz tube is thus dispensed with according to the invention, in that the receiving space is designed to receive the protective gas and the coated glass fiber in direct contact with one another, the corresponding disadvantages described above can be avoided.

According to a further aspect of the invention, the curing device has a first curing unit with a first receiving half-space and a second curing unit with a second receiving half-space, the first receiving half-space of the first curing unit and the second receiving half-space of the second curing unit being designed to jointly form the receiving space of the curing device , and wherein the first curing unit and the second curing unit are designed to be movable relative to one another, preferably translationally, in order to open and close the receiving space of the curing device. Both recording half-spaces can have a semi-circular, oval, triangular, rectangular, quadrangular, hexagonal, other polygonal or other horizontal contour which is suitable for implementing the relevant aspects of the invention. The contour can be consistently the same or different in the vertical direction.

In other words, the curing device or a component of the curing device can be designed in at least two parts such that the two curing units can be moved relative to one another or relative to another component in such a way that the receiving space can be closed or opened and made accessible. This can be done through a purely translational movement of at least one curing unit relative to the other evaluation unit or another component or both curing units relative to each other or another component, which can keep the implementation of the movement simple. Alternatively, however, a rotational movement, a pivoting movement or a combined rotational and translational movement can also be used for this purpose. In any case, in this way the receiving space can be opened and closed around a coated glass fiber located there, which can be easier than guiding an open end of a coated glass fiber through an upper opening of the receiving space in preparation for the manufacturing process.

The two curing units can preferably be configured identically, so that one type of curing unit can be used twice. This can reduce the manufacturing cost.

According to a further aspect of the invention, at least one protective gas opening for inflow is arranged on the first curing unit and at least one protective gas opening for escaping is arranged on the second curing unit. This can favor the uniformity of the flow of shielding gas. In this way, in particular, the design options for the flow of the protective gas can be increased.

According to a further aspect of the invention, the UV radiation sources are UV LEDs. In this way, the properties and advantages of UV LEDs can be used in the curing device according to the invention. This can include a comparatively low consumption of electrical energy, comparatively little waste heat, also to protect the coating and/or the glass fiber core of the glass fiber, and associated with it a comparatively high energy efficiency, a comparatively compact installation space and/or a comparatively long service life .

According to a further aspect of the invention, the UV LEDs are, preferably precisely, designed as a first plurality of UV LEDs, preferably of the first curing unit, and as a second plurality of UV LEDs, preferably of the second curing unit, with the two pluralities of UV LEDs extend linearly in the direction of movement of the coated glass fiber and/or the two pluralities of UV LEDs are arranged diametrically opposite one another perpendicularly to the direction of movement of the coated glass fiber.

The use of a plurality of UV LEDs along the moving direction of the coated optical fiber can be used to cure the coating of the optical fiber by UV light over a correspondingly long distance, which can increase the curing efficiency. Arranging the UV LEDs in a line along the direction of movement of the coated glass fiber can simplify the manufacture of the curing device. In this way, the use of optical images for the purpose of beam shaping and/or beam deflection can also be dispensed with, so that the coating of the glass fiber can be effectively irradiated with UV light without adjusting the coated glass fiber in a superimposition of the UV radiation can. In this way, an adjustment-free system can be created, which means that corresponding adjustment errors or operating errors can be ruled out and faulty production caused thereby can be avoided.

Arranging the at least two pluralities of UV LEDs diametrically opposite each other perpendicular to the direction of movement of the coated glass fiber can ensure that the coating of the glass fiber can be irradiated and cured with UV light from at least two opposite sides, which can lead to sufficient curing . If exactly two pluralities of UV LEDs are used in this arrangement, the desired curing can be sufficiently effected due to the avoidance of optical imaging losses and the effort for this can be kept comparatively low, since almost all of the emitted primary radiation of the UV light can be used for curing . This can keep the acquisition costs of the UV LEDs and their energy consumption low. The curing device according to the invention can be operated correspondingly economically and inexpensively, which can keep the production costs of the glass fiber low.

Additionally or alternatively, the present invention relates to a curing device for coatings of glass fibers with a receiving space for guiding a coated glass fiber through in a direction of movement, the receiving space having a plurality of UV radiation sources which are designed to cure the coating of the glass fibers using UV light , Like previously described.

The curing device is characterized in that the curing device is designed to control the temperature of the UV radiation sources by means of a fluid, preferably to cool them, with the fluid being guided outside the receiving space. In other words, the fluid can be guided into the area of the UV radiation sources and have a temperature-controlling effect on the UV radiation sources without being guided or conveyed into the receiving space. In this way, the corresponding temperature-controlling effect on the UV radiation sources can be achieved without, however, requiring space in the recording room for this. Accordingly, the receiving space can be kept comparatively small, so that the UV radiation sources can be arranged as close as possible to the coated glass fiber, which can increase the effectiveness of the UV radiation or keep the radiation energy required for this low.

By tempering and in particular by cooling the UV radiation sources, at least an impermissibly high heating or overheating of the UV radiation sources can be avoided, which can increase the service life or availability of the UV radiation sources. The present invention is also based on the knowledge that, particularly in the case of UV LEDs as UV radiation sources, there can be a shift in the wavelength of the UV radiation generated as a function of its temperature. Thus, in particular by cooling the UV radiation sources, in particular as UV LEDs, to their predetermined operating temperature, it can be achieved that the UV radiation is generated and emitted with the predetermined wavelength. This ensures that the UV radiation can have the appropriate effect on the coating of the glass fiber. In other words, the wavelength of the generated UV radiation can be stabilized at its operating point. This can have a correspondingly positive effect on the process of curing the coating of the glass fiber, since effective curing over the entire process can be brought about by appropriately efficient absorption of the UV radiation by the phonoinitiators contained in the coating material.

Furthermore, by tempering the UV radiation sources, the UV radiation sources and in particular the UV LEDs can be operated at a predetermined temperature, as a result of which the wavelength of the UV radiation sources generated can be influenced in a targeted manner. As a result, the wavelength of the UV radiation generated can be specifically influenced via the temperature of the UV radiation sources, which occurs due to their operation or the electrical heating and tempering caused by this on the part of the curing device. Correspondingly, the wavelength of the generated UV radiation can be specified as primary radiation to a certain extent by specifically setting or regulating the temperature of the UV radiation sources, preferably as a function of a temperature detected by sensors, as will be described in more detail below. Accordingly, the curing device according to the invention can be adjusted, preferably as optimally as possible, to different materials of the coating of the glass fiber, which can be effectively cured at different wavelengths of UV radiation.

According to one aspect of the invention, the UV radiation sources are arranged on a housing and the housing has at least one fluid line which is formed adjacent to at least one of the UV radiation sources such that the fluid has a temperature-controlling, preferably cooling, effect on the UV radiation source can work. This can simplify the implementation of guiding the fluid.

According to a further aspect of the invention, the housing is designed to be comparatively well thermally conductive, at least directly between the fluid line and the UV radiation source. A material with comparatively good thermal conductivity is to be understood as meaning that the material of the housing has a comparatively high coefficient of thermal conductivity, at least in this area, compared to the other areas of the housing. As a result, a transfer or an effect of the temperature of the fluid on the UV radiation source can be accelerated or promoted, so that its temperature can be influenced quickly and directly. According to a further aspect of the invention, there is at least one temperature sensor which is designed to detect the temperature in the receiving space, with the curing device being designed to regulate the temperature of the fluid depending on the detected temperature of the receiving space. Such a temperature measurement or temperature detection of the temperature sensor can take place, for example, via a temperature-dependent electrical resistance.

In this way, a temperature of the UV radiation sources can be inferred from a sensor-detected temperature of the gas or the protective gas in the receiving space of the curing device, in order to at least prevent them from overheating. This can improve the service life or availability of the UV radiation sources, as described above.

According to a further aspect of the invention, the curing device has at least one temperature sensor which is designed to detect the temperature of at least one of the UV radiation sources, the curing device being designed to regulate the temperature of the fluid depending on the detected temperature of the UV radiation source. Such a temperature measurement or temperature detection of the temperature sensor can take place, for example, via a temperature-dependent electrical resistance. This can make it possible to control or regulate the cooling of the UV radiation sources and in particular the targeted temperature control of the UV radiation sources as a function of their sensor-detected temperature. As already described above, this can at least serve to prevent overheating of the UV radiation sources. Additionally or alternatively, the sensed temperature can be used to operate the UV radiation source at a predetermined temperature with a corresponding predetermined wavelength of the generated UV radiation, as previously described.

According to a further aspect of the invention, the curing device is designed to temper the UV radiation sources by means of the fluid in such a way that they emit a predetermined wavelength. As a result, the corresponding properties and advantages described above can be implemented.

According to a further aspect of the invention, the curing device has a first curing unit with a first receiving half-space and a second curing unit with a second receiving half-space, the first receiving half-space of the first curing unit and the second receiving half-space of the second curing unit being designed to jointly form the receiving space of the curing device , and wherein the first curing unit and the second curing unit are designed to be movable relative to one another, preferably translationally, in order to open and close the receiving space of the curing device. To avoid repetition, reference is made to the preceding corresponding explanations. According to a further aspect of the invention, at least one UV radiation source is arranged on the first curing unit and at least one UV radiation source is arranged on the second curing unit. This can promote uniformity in the generation of UV radiation. In this way, in particular, the design options for generating the UV radiation can be increased.

According to a further aspect of the invention, at least one fluid line is arranged on the first curing unit and at least one fluid line is arranged on the second curing unit. This can favor the uniformity of the temperature control of the UV radiation sources. In this way, in particular, the design options for temperature control of the UV radiation sources can be increased

According to a further aspect of the invention, the UV radiation sources are UV LEDs. To avoid repetition, reference is made to the preceding corresponding explanations.

According to a further aspect of the invention, the UV LEDs are, preferably precisely, designed as a first plurality of UV LEDs, preferably of the first curing unit, and as a second plurality of UV LEDs, preferably of the second curing unit, with the two pluralities of UV LEDs extend linearly in the direction of movement of the coated glass fiber and/or the two pluralities of UV LEDs are arranged diametrically opposite one another perpendicularly to the direction of movement of the coated glass fiber. To avoid repetition, reference is made to the preceding corresponding explanations.

According to a further aspect of the invention, at least several UV LEDs, preferably all UV LEDs, each have a temperature sensor which is designed to detect the temperature of the UV LED, with the curing device being designed to use the fluid as a function of the to temper the detected temperature of the UV LEDs, preferably to temper in such a way as to emit a predetermined wavelength. As a result, the accuracy of the sensory detection of the temperatures of the UV LEDs can be increased in order to be able to achieve a correspondingly precise temperature control or cooling of the UV LEDs.

An exemplary embodiment and further advantages of the invention are shown purely schematically and explained in more detail below in connection with the following figures. It shows:

FIG. 1 shows a perspective view of a curing device according to the invention with the receiving space open;

FIG. 2 shows the representation of FIG. 1 with the receiving space closed;

FIG. 3 shows a plan view of the curing device with the receiving space closed;

FIG. 4 shows a front view of the curing device with the receiving space closed;

Figure 5 is a sectional view of Figure 4; FIG. 6 shows a detailed view of the upper central area of FIG. 5;

FIG. 7 shows a side view of a first curing unit of the curing device;

FIG. 8 shows a detailed view of the upper central area of FIG. 7;

FIG. 9 shows a detailed view of the central region of FIG. 3 as a first horizontal section; and FIG. 10 shows a detailed view of the middle area of FIG. 3 as a second horizontal section.

The above figures are viewed in Cartesian coordinates. A longitudinal direction X, which can also be referred to as depth X or length X, extends. A transverse direction Y, which can also be referred to as width Y, extends perpendicularly to the longitudinal direction X. A vertical direction Z, which can also be referred to as the height Z and corresponds to the direction of gravity, extends perpendicularly both to the longitudinal direction X and to the transverse direction Y. The longitudinal direction X and the transverse direction Y together form the horizontal X, Y, which can also be referred to as the horizontal plane X, Y.

A curing device 1, 2 according to the invention for coating glass fibers 4 has a first curing unit 1 and a second curing unit 2, which are of identical design. The two curing units 1, 2 can each also be referred to as curing modules 1, 2. The two curing units 1, 2 together enclose a receiving space 11, 21, through which a coated glass fiber 4 can be guided in the vertical direction Z from top to bottom in a movement direction A as part of a manufacturing process. In addition to the two curing units 1, 2, the curing device 1, 2 according to the invention also has rails 3, various fluid and protective gas hoses, electrical supply lines, data and control cables, a control unit and other components, as will be explained in more detail below, which however, are not shown for the sake of clarity and clarity of the figures.

The coated glass fiber 4 is drawn from a preform, which is why the direction of movement A can also be referred to as the drawing direction A. This is done using a fiber drawing tower (not shown) of a production plant for coated glass fibers 4 in the vertical direction Z from top to bottom by appropriately heating the preform, which is then provided with a coating of plastic such as polyamide, acrylic or silicone or . To cure the coating of the glass fiber 4 using UV light, the coated glass fiber 4 is guided through the receiving space 11, 21 of the curing device 1, 2 and is irradiated using UV light, as will be described in more detail below. The coated glass fiber 4 can then be rolled up with the hardened coating.

As already mentioned above, the two curing units 1, 2 are of identical design, so that the first curing unit 1 is essentially described in detail below and this applies correspondingly to the second curing unit 2. The first curing unit 1 has a housing 10 which closes off the first curing unit 1 on the outside and which essentially accommodates its elements on the inside. The housing 10 is essentially cuboid and has a semi-circular indentation facing the second curing unit 2 in the transverse direction Y, which forms a first receiving half-space 11 of the first curing unit 1 . The first receiving half-space 11 of the first curing unit 1 and the corresponding second receiving half-space 21 of the housing 20 of the second curing unit 2 form the cylindrical receiving space 11, 21 of the curing device 1, 2 in the closed state Glass fiber 4 along the longitudinal axis or central axis (not labeled) of the cylindrical receiving space 11, 21 out through this in the vertical direction Z from top to bottom.

A plurality of UV radiation sources 12 in the form of UV LEDs 12 are arranged linearly one above the other in the vertical direction Z in the middle of the semicircular arc-shaped first recording half-space 11, which can therefore also be referred to as a UV LED row 12. The corresponding UV LEDs 22 of the second curing unit 2 are diametrically opposed to the UV LEDs 12 of the first curing unit 1 with respect to the coated glass fiber 4 or to the longitudinal axis of the cylindrical receiving space 11 , 21 . In this way, the coating of the glass fiber 4 can be irradiated from both sides with UV light as the primary radiation B and thereby hardened. The speed of movement of the coated glass fiber 4 can be matched to the number or the power of the UV LEDs 12, 22 in the vertical direction Z in such a way that the coated glass fiber 4 when exiting the receiving space 11, 21 of the curing device 1, 2 has a fully cured coating.

Compared to known curing devices 1, 2 for coating glass fibers 4, there is no need to adjust the coated glass fiber 4 relative to the usually tubular UV radiation sources, which means that the effort involved in adjustment or adjustment and the errors caused thereby can be avoided. The advantageous properties of UV LEDs 12, 22 such as comparatively low energy consumption, comparatively low heat loss, comparatively small installation space, comparatively little heating of the coating of the coated glass fiber 4 and/or a comparatively long service life can also be used.

In order to be able to operate the UV LEDs 12, 22 of the two curing units 1, 2 during operation at a predetermined temperature and at least to protect them from overheating, the curing device 1, 2 according to the invention has two fluid lines running in the vertical direction Z per curing unit 1, 2 13a, 23a as cooling water lines 13a, 23a, which are each formed cylindrical and extend proximate the UV LEDs 12,22 within the housing 10,20. The area of the curing unit 1, 2 between the fluid lines 13a, 23a and the UV LEDs 12, 22 is in each case formed by a particularly good thermally conductive material in order to transfer the heat away from the UV LEDs 12, 22 into the area of the To favor fluid lines 13a, 23a, or vice versa.

The cooling water lines 13a, 23a each have fluid connections 13 in the form of cooling water connections 13, 23 at their ends. The total of eight cooling water connections 13, 23 are each connected to flexible hoses. Cooling water can be fed to the two curing units 1 , 2 as a fluid via half of the cooling water connections 13 , 23 . After flowing through the respective curing unit 1, 2, the cooling water can be discharged from the other half of the cooling water connections 13, 23 and, if necessary, cooled down or tempered again. The cooling water can be supplied or removed from the curing device 1, 2 by means of appropriate pumps, hoses and heat exchangers and the like (not shown).

In the simplest case, the heat generated by the UV LEDs 12, 22 during operation can be dissipated to a certain extent in this way via the cooling water in order to increase the longevity of the UV LEDs 12, 22 or to avoid overheating of the UV LEDs 12, 22, which could lead to damage or even destruction of the UV LEDs 12, 22. Depending on the temperature and flow rate of the cooling water, at least a certain stable operating point can be achieved during the operation of the curing device 1, 2 or during the manufacturing process of the coated glass fiber 4.

In addition, the curing device 1, 2 according to the invention is based on the finding that the wavelength of the primary radiation B emitted by UV LEDs 12, 22 can be influenced by its operating temperature. Thus, since a stable operating point can be achieved during the manufacturing process of the coated glass fiber 4 by cooling with cooling water, the wavelength of the emitted primary radiation B of the UV light can also be kept stable.

In addition, this relationship between the wavelength of the primary radiation B emitted by the UV LEDs 12, 22 and its operating temperature can be used to keep the UV LEDs 12, 22 within a certain range by controlling the temperature of the cooling water to a predetermined temperature to operate with a predetermined wavelength. For this purpose, a temperature sensor 15, 25 is arranged immediately next to each UV LED 12, 22 of both curing units 1, 2, so that a temperature in the immediate vicinity of each UV LED 12, 22 can be detected by sensors via the temperature sensors 15, 25 , Which of the respective UV-LED 12, 22 can be attributed. By means of a control unit (not shown) of the curing device 1, 2, the temperatures of all UV LEDs 12, 22 can thus be detected and compared to a predetermined th temperature, which corresponds to a predetermined wavelength of the primary radiation B, can be used to control the temperature and/or the flow rate of the cooling water. The temperature of the cooling water can therefore also be comparatively high and for this purpose the cooling water can even be heated by the curing device 1, 2 in order to be able to set the predetermined wavelength of the primary radiation B. Correspondingly, instead of cooling the UV LEDs 12, 22, one can also speak of temperature control of the UV LEDs 12, 22, since the cooling water or the fluid can also be heated.

This can make it possible to influence the wavelength of the primary radiation B in a predetermined manner solely by controlling the temperature of the fluid or the cooling water. As a result, the UV LEDs 12, 22 can be operated to a certain extent with different predetermined wavelengths of the primary radiation B, so that different coatings of the glass fiber 4 can be used and cured effectively by means of the UV light of the primary radiation B.

The two curing units 1, 2 also each have two protective gas lines 14a, 24a, which can also receive or release a protective gas at both ends via protective gas connections 14, 24. The total of eight protective gas connections 14, 24 are each connected to other components of the curing device 1, 2 via a flexible hose, so that a protective gas such as nitrogen is made available from a source such as a tank (not shown) and by means of at least one Pump (not shown) half of the protective gas lines 14a, 24a can be supplied by funding. In comparison, the other half of the protective gas lines 14a, 24a lead via hoses to at least one pump (not shown), which sucks in the protective gas and can discharge it into a reservoir (not shown).

The total of four protective gas lines 14a, 24a run in the vertical direction Z parallel to the respective receiving half-space 11, 21 of the respective curing unit 1, 2. Two protective gas branches 14b, 24b in a straight line or radially away from the respective protective gas lines 14a, 24a and each open out in the form of a protective gas opening 14c, 24c into the respective receiving half-space 11, 21. If the corresponding protective gas line 14a, 24a is supplied with the protective gas, the protective gas can flow through all the protective gas openings 14c , 24c, which are connected to this protective gas line 14a, 24a via the protective gas branches 14b, 24b, reach the corresponding receiving half-space 11, 21. These inert gas openings 14c, 24c can correspondingly be referred to as inert gas openings 14c, 24c for inflow or also as inert gas inlets 14c, 24c. If the protective gas is discharged or sucked out of the corresponding receiving half-space 11, 21 via the corresponding protective gas line 14a, 24a, these protective gas openings 14c, 24c can be referred to as protective gas openings 14c, 24c for escaping or as protective gas outlets 14c, 24c. The configuration of the two curing units 1, 2 with regard to the protective gas openings 14c, 24c, which are used to flow in and suck off the protective gas into the receiving space 11, 21 of the curing device 1, 2, can be done quickly and easily by connecting the hoses for guiding the protective gas be made or changed. For example, per curing unit 1, 2, one protective gas line 14a, 24a can be used for the inflow and the other protective gas line 14a, 24a for the protective gas to escape. This can be done crosswise in the horizontal X, Y, for example, so that, viewed in the circumferential direction around the coated glass fiber 4, the protective gas openings 14c, 24c for inflow and the protective gas openings 14c, 24c for escaping alternate.

In this way, according to the invention, the protective gas can be distributed as evenly as possible over the entire receiving space 11, 21 of the curing device 1, 2, both in the vertical direction Z and within the horizontal planes X, Y, and fed to the coated glass fiber 4 in order to facilitate the curing of the To be able to coat the glass fiber 4 in a protective gas environment that is as uniform as possible. This can improve the quality of the cured coating of the glass fiber 4. At the same time, the protective gas, including the noxious vapors that may arise during the process of curing the coating of the glass fiber 4, can be prevented from escaping, discharging or sucking off the protective gas from the receiving space 11, 21 into the surroundings of the curing units 1, 2 can.

In addition, the temperature of the protective gas inside the receiving space 11, 21 can also be detected by means of the temperature sensors 15, 25 described above. On the part of the curing device 1, 2, the protective gas can be heated to a predetermined temperature before it flows into the receiving space 11, 21, which can promote the curing of the coating of the glass fiber 4. As a result, the reaction speed or the polymerization speed of the coating of the glass fiber 4 can be influenced and, in particular, increased by an increased temperature. This can make it possible to increase the speed of drawing the glass fiber 4 from the preform and thereby the production speed of the coated glass fiber 4, which can lead to increased productivity of the entire manufacturing process and thus to reduced production costs of the coated glass fiber 4.

To operate the two curing units 1, 2, they can be connected via control lines (not shown) to control connections 16, 26 of their housings 10, 20 with the control unit of the curing device 1, 2 in a signal-transmitting manner. As a result, at least the temperature sensors 15, 25 and the UV LEDs 12, 22 can be operated and controlled. The two curing units 1, 2 can also be connected to the control unit of the curing device 1, 2 or to the control unit of the curing device 1, 2 or to be connected to any other electrical energy supply source in order to be able to supply electricity to at least the temperature sensors 15, 25 and the UV LEDs 12, 22.

In order to be able to make the receiving space 11, 21 of the curing device 1, 2 more easily accessible, the two curing units 1, 2 are each movably arranged on a common pair of rails 3, which extends horizontally in the transverse direction Y. The rails 3 can be arranged in a stationary manner on a frame of the fiber drawing tower, so that the two curing units 1, 2 each extend outwards in the transverse direction Y away from the longitudinal axis of the coated glass fiber 4, relative to the longitudinal axis of the coated glass fiber 4 running in the vertical direction Z, or can be proceeded towards this. The two curing units 1, 2 can be moved by electric drives of the curing units 1, 2, which can also be operated and controlled or electrically supplied by the control unit of the curing device 1, 2, as described above. However, such electrical drives can be provided on the side of the rails 3 in order to keep the effort and the weight of the two curing units 1, 2 low.

If the two curing units 1, 2 are moved towards the longitudinal axis of the coated glass fiber 4, the receiving space 11, 21 can be closed as a result. In this position, the two curing units 1, 2 can also be secured mechanically on the outside of their housings 10, 20 (not shown). In this state, the manufacturing process of the coated glass fiber can be carried out as described above. Gas-tight sealing of the closed receiving space 11, 21 in the longitudinal direction X can be ensured by seals made of rubber, for example, running in the vertical direction Z.

If the two curing units 1, 2 are moved away from one another in the transverse direction Y, the receiving space 11, 21 can be opened as a result. The two receiving half-spaces 11, 21 of the two curing units 1, 2 are sufficiently spaced apart from one another in the transverse direction Y, so that a coated glass fiber 4 can be positioned in the longitudinal direction X between the two receiving half-spaces 11, 21 of the two curing units 1, 2. In this way it can be avoided that a coated glass fiber 4 has to be introduced in the vertical direction Z from above into a permanently closed receiving space of a known curing device, which can be comparatively costly and complicated. LIST OF REFERENCE NUMBERS (part of the description)

A direction of movement; drag direction

B primary radiation

X longitudinal direction; Depth; length

Y transverse direction; Broad

Z vertical direction; Height

X, Y Horizontal; horizontal plane

I, 2 Glass fiber coating curing device 4

II, 21 recording room

1 first curing unit; first curing module

10 housing

11 first recording hemisphere

12 UV radiation source; UV LEDs; UV LED series

13 fluid ports; cooling water connections

13a fluid lines; cooling water pipes

14 shielding gas connections

14a protective gas lines

14b inert gas branches

14c protective gas openings; protective gas inlets; shielding gas outlets

15 temperature sensors

16 control ports

17 electrical supply connections

2 second curing unit; second curing module

20 housing

21 second recording hemisphere

22 UV radiation source; UV LEDs; UV LED series

23 fluid ports; cooling water connections

23a fluid lines; cooling water pipes

24 shielding gas connections

24a protective gas lines

24b inert gas branches c protective gas openings; protective gas inlets; shielding gas outlets temperature sensors control connections electrical supply connections rails coated glass fiber

Claims

TI CLAIMS

1. Curing device (1, 2) for coatings of glass fibers (4) with a receiving space (11, 21) for passing a coated glass fiber (4) in a direction of movement (A), wherein the receiving space (11, 21) has a plurality of UV - Has radiation sources (12, 22) which are designed to harden the coating of the glass fiber (4) by means of UV light, characterized in that the receiving space (11, 21) has at least one protective gas opening (14c, 24c) which is designed is to allow a protective gas to flow into the receiving space (11, 21), preferably by conveying the curing device (1, 2), and the receiving space (11, 21) has at least one protective gas opening (14c, 24c), which is designed allowing the protective gas to escape from the receiving space (11, 21), preferably by sucking off the curing device (1, 2).

2. Curing device (1, 2) according to claim 1, characterized in that the protective gas opening (14c, 24c) for inflow and the protective gas opening (14c, 24c) for escaping in the direction of movement (A) of the coated glass fiber (4) are arranged offset to one another are.

3. Curing device (1, 2) according to claim 1 or 2, characterized in that the receiving space (11, 21) has at least one protective gas opening (14c, 24c), which is designed to allow the protective gas, preferably by conveying the curing device (1, 2) to flow into the receiving space (11, 21), and the receiving space (11, 21) has at least two protective gas openings (14c, 24c), which are designed to allow the protective gas to flow, preferably by suction from the curing device (1, 2) to let it escape from the receiving space (11, 21), the protective gas opening (14c, 24c) for flowing in in the direction of movement (A) of the coated glass fiber (4) between the two protective gas openings (14c, 24c) for escaping, preferably in the middle, is arranged.

4. Curing device (1, 2) according to one of the preceding claims, characterized in that the receiving space (11, 21) has at least two protective gas openings (14c, 24c), which are designed to convey the protective gas, preferably by conveying the curing device (1, 2) to flow into the receiving space (11, 21), and the receiving space (11, 21) has at least one protective gas opening (14c, 24c), which are designed to allow the protective gas to flow, preferably by suction from the curing device (1, 2) to let it escape from the receiving space (11, 21), the protective gas opening (14c, 24c) for escaping in the direction of movement (A) of the coated glass fiber (4) between the two protective gas openings (14c, 24c) for inflow, preferably in the middle, is arranged.

5. Curing device (1, 2) according to Claim 1, characterized in that the protective gas opening (14c, 24c) for inflow and the protective gas opening (14c, 24c) for escaping are in the same plane perpendicular to the direction of movement (A) of the coated glass fiber (4) are arranged.

6. Curing device (1, 2) according to claim 5, characterized in that the protective gas opening (14c, 24c) for inflow and the protective gas opening (14c, 24c) for escaping are arranged diametrically opposite one another to the direction of movement (A) of the coated glass fiber (4). are.

7. Curing device (1, 2) according to claim 5 or 6, characterized in that the receiving space (11, 21) has at least two protective gas openings (14c, 24c), which are designed to allow the protective gas, preferably by conveying the curing device (1, 2) to flow into the receiving space (11, 21), and the receiving space (11, 21) has at least two protective gas openings (14c, 24c), which are designed to allow the protective gas to flow, preferably by suction from the curing device (1, 2) , from the receiving space (11, 21), wherein the protective gas openings (14c, 24c) for inflow and the protective gas opening (14c, 24c) for escaping in the same plane perpendicular to the direction of movement (A) of the coated glass fibers (4) are arranged alternately to one another, preferably evenly spaced from one another.

8. Curing device (1, 2) according to one of the preceding claims, characterized in that the receiving space (11, 21) has at least two protective gas openings (14c, 24c), which are designed to convey the protective gas, preferably by conveying the curing device (1, 2) to flow into the receiving space (11, 21), the protective gas openings (14c, 24c) for the inflow being arranged linearly offset in the direction of movement (A) of the coated glass fiber (4), and/or the receiving space (11 , 21) has at least two protective gas openings (14c, 24c), which are designed to allow the protective gas to escape from the receiving space (11, 21), preferably by suction from the curing device (1, 2), the protective gas openings (14c, 24c ) for escaping in the direction of movement (A) of the coated glass fiber (4) are arranged offset to one another in a linear manner.

9. Curing device (1, 2) according to claim 7 or 8, characterized in that the at least two protective gas openings (14c, 24c) are connected to a common protective gas line (14a, 24a) for inflow, the at least two protective gas openings (14c, 24c) are connected to a common protective gas line (14a, 24a) for escaping, and the curing device (1, 2) is designed so that the protective gas flows in the opposite direction or in the same direction through the protective gas line (14a, 24a) of the protective gas openings (14c, 24c). and through the protective gas line (14a, 24a) of the protective gas openings (14c, 24c) to escape.

10. Curing device (1, 2) according to one of the preceding claims, characterized in that the inert gas opening (14c, 24c) for inflow and/or the inert gas opening (14c, 24c) for escape is perpendicular to the direction of movement (A) of the coated glass fiber (4th ) are aligned. Curing device (1, 2) according to one of the preceding claims, characterized in that the receiving space (11, 21) has at least one temperature sensor (15, 25) which is designed to detect a temperature of the protective gas, and the curing device (1, 2) is designed to regulate the temperature of the inflowing protective gas depending on the detected temperature of the protective gas in the receiving space (11, 21). Curing device (1, 2) according to one of the preceding claims, characterized in that the receiving space (11, 21) is designed to receive the protective gas and the coated glass fiber (4) in direct contact with one another. Curing device (1, 2) according to one of the preceding claims, characterized in that the curing device (1, 2) has a first curing unit (1) with a first receiving half-space (11) and a second curing unit (2) with a second receiving half-space (21) wherein the first half-receiving space (11) of the first curing unit (1) and the second half-receiving space (21) of the second hardening unit (2) are designed to jointly form the receiving space (11, 21) of the hardening device (1, 2), and wherein the first curing unit (1) and the second curing unit (2) are designed to be movable relative to one another, preferably translationally, in order to open and close the receiving space (11, 21) of the curing device (1, 2). Curing device (1, 2) according to Claim 13, characterized in that at least one protective gas opening (14c, 24c) for inflow is arranged on the first curing unit (1) and at least one protective gas opening (14c, 24c) for escaping is arranged on the second curing unit (2). is. Curing device (1, 2) according to one of the preceding claims, characterized in that the UV radiation sources (12, 22) are UV LEDs (12, 22). 31 curing device (1, 2) according to claim 15, characterized in that the UV LEDs (12, 22), preferably precisely, as a first plurality of UV LEDs (12), preferably the first curing unit (1), and as a second plurality UV LEDs (22), preferably the second curing unit (2), are formed, with the two pluralities of UV LEDs (12, 22) each extending linearly in the direction of movement (A) of the coated glass fiber (4) and/or wherein the two pluralities of UV LEDs (12, 22) are arranged diametrically opposite one another perpendicularly to the direction of movement (A) of the coated glass fiber (4).