Connectors with protective sleeve

Abstract

The invention relates to a connector (10) for the detachable connection of optical fibers (20), wherein the connector (10) comprises a ferrule (14) formed with a through-opening (12) for receiving and positioning a connection end (16) of an optical fiber (18) of an optical fiber (20), and wherein the connector (10) has a protective sleeve (22) which can be connected to the end (24) of the ferrule (14) near the connection end (16) of the optical fiber (18). The invention further relates to an optical fiber configuration (60) comprising a connector (10) and an optical fiber (20) attached thereto, as well as a method for manufacturing them.

Description

The invention relates to a plug connector for the detachable connection of optical waveguides according to the preamble of claim 1.Plug connectors for the detachable connection of optical waveguides or glass fiber cables are used to form a plug-and-plug connection or also a plug-and-socket connection. The plug connectors should have the lowest possible power losses. The known plug connectors essentially have at least one ferrule, wherein the ferrule serves to receive a fiber end of an optical fiber of an optical fiber. Furthermore, the ferrule can also be designed such that the optical waveguide itself or a jacket of the optical waveguide can be fixed to the ferrule, for example by means of crimping, collet chuck or adhesive bonding by means of adhesive material. The ferrule has a through hole into which the optical fiber connecting end of the optical fiber is inserted and positioned opposite to a fiber end of an opposite connector or a socket. In this case, the most coaxial possible arrangement of the through bore or of the fiber end is stressed in the ferrule, so that the ferrule can meet particularly high accuracy requirements. Also, when absorbing light power, the optical fiber can be thermally damaged, for example by adhesive material on the optical fiber or residues of polishing wax and other impurities. The ferrule must therefore be designed such that it is not damaged in the region of the end face of the ferrule and the connecting end of the fiber by, for example, a burning-off of material residues. Moreover, this connecting end of the fiber must be polished to meet the requirements of accuracy. However, since the connecting end of the fiber at the end of the ferrule is free in the manner of the species, vibrations of the free-standing fiber end occur during polishing of the optical fibers of plug connectors of the type in question. These vibrations of the fiber end are disadvantageous and undesirable during polishing. In order to avoid this, the pure optical fiber can be polished beforehand, for example, and only subsequently inserted into the plug connector, wherein damage can arise, however, when the polished fiber is inserted. It is therefore more advantageous to introduce the fiber first into the plug connector and subsequently polish it. For this purpose, it is known from the prior art to fill the end of the ferrule, in which the connecting end of the optical fiber is free, with a polishing wax for polishing in order to avoid oscillations of the free-standing fiber end. However, the polishing wax must be removed after polishing in a complicated manner for this purpose. Moreover, no polishing wax residues must remain on the optical fiber, since these could lead to burn-up.The object of the present invention is therefore to propose a plug connector and an optical waveguide configuration which enable a low-cost, error-prone and precise polishing of the connection end of an optical fiber of a plug connector.In addition, a method is to be proposed which enables the production of an optical waveguide configuration with low outlay and reduced costs with simultaneous resource conservation.This object is achieved by a plug connector having the features of claim 1 and an optical waveguide configuration having the features of claim 14. In addition, the object is achieved by a method for producing an optical waveguide configuration having the features of claim 16.The plug connector according to the invention for the detachable connection of optical waveguides comprises a ferrule formed with a through-opening for receiving and positioning a connection end of an optical fiber of an optical waveguide. The connector is characterized in that a protective sleeve of the connector is connectable to the end of the ferrule near the connection end of the optical fiber.The through-opening of the ferrule is preferably formed as a through-bore.The connecting end of the optical fiber of the optical fiber is, within the scope of the invention, the free end of the optical fiber which is to be connected to a further optical fiber of a plug connector or a socket.Protective sleeve and ferrule can be connected, preferably directly, to two individual elements of the plug connector. The protective sleeve can be permanently connectable to the ferrule by means of pressing and / or adhesive bonding. However, it has proven advantageous if the protective sleeve can be detachably connected to the ferrule. A detachable connection is, within the scope of the invention, a connection which can be detached in a non-destructive manner, in particular without damage to the ferrule. Preferably, the releasable connection is force-fit and / or form-fit. Further preferably, the protective sleeve can be repeatedly connected to the ferrule. In other words, this means that the protective sleeve can be removed from the ferrule and subsequently arranged again on the ferrule.The longitudinal axes of the ferrule and the longitudinal axis of the protective sleeve preferably coincide. As a result, the optical fiber is centered both in the protective sleeve and in the ferrule. If the ferrule and the protective sleeve are rotationally symmetrical bodies, the axis of rotation of the ferrule can coincide with the axis of rotation of the protective sleeve.The plug connector can be inserted with the protective sleeve in front into a socket for plug-socket connection or can be connected to a further plug connector for plug-plug connection. Because the protective sleeve can be connected to the ferrule, it can be removed from the ferrule for polishing the connecting end of the optical fiber and arranged on the ferrule after the polishing process, preferably pushed onto the ferrule. By pushing the fiber out of the ferrule into the protective sleeve, the fiber can be adjusted within the protective sleeve. After adjusting the fiber in the protective sleeve, a plug connector is formed for the detachable connection of optical fibers. In contrast to prior art solutions which provide for the filling of one end of the ferrule with polishing wax or the use of a disposable sleeve during the polishing process, the protective sleeve according to the invention is part of the plug connector according to the invention, whereby resources can be saved and assembly costs can be reduced. Furthermore, the ferrule itself may form an auxiliary stopper for polishing the connecting end of the optical fiber, so that the connecting end of the optical fiber is held by the ferrule during the polishing process, and no polishing wax or another ferrule to be disposed of possibly after the polishing process becomes necessary. Thus, it can be ensured, on the one hand, that no oscillations occur at the connecting end of the optical fiber during the polishing process and, in addition, that no material residues, for example of polishing wax, have to be removed after the polishing process or remain on the optical fiber in a disadvantageous manner.The ferrule, the fastening sleeve or further components of the plug connector, such as the protective sleeve, for example, can be formed from a metal, preferably a copper alloy or a copper-nickel-zinc alloy. Nevertheless, the locking sleeve can also be formed from this or another metal. It is also possible to form the locking sleeve and / or the fastening sleeve from a plastic material.The end of the ferrule close to the connecting end of the optical fiber is, within the scope of the invention, the end of the ferrule from which the free end of the optical fiber, i.e. the connecting end of the optical fiber, exits. On the other hand, the end of the ferrule remote from the connecting end of the optical fiber is the end of the ferrule into which the optical fiber and / or the optical fiber is inserted to pass the optical fiber through the ferrule.Advantageous embodiments of the invention are the subject of the dependent claims. Moreover, all combinations of at least two features disclosed in the description, the claims and / or the figures fall within the scope of the invention. It is understood that the embodiments made for the plug connector relate equivalently to the optical waveguide configuration according to the invention and to the method according to the invention, without being mentioned separately for these. In this case, it is understood in particular that standard language transformations and / or a corresponding replacement of respective terminology within the scope of conventional language practice, in particular the use of synonyms protected by the generally accepted language literature, are encompassed by the present disclosure content without being explicitly mentioned in their respective embodiment.The protective sleeve can be detachably connected to the ferrule by means of a snap-in connection and / or by means of a screw connection. To form a latching connection between the protective sleeve and the ferrule, the protective sleeve or the ferrule can have a latching nose which engages behind a diameter shoulder of the ferrule or the protective sleeve in order to releasably secure the protective sleeve to the ferrule. For example, the ferrule can have a latching nose, which engages behind a diameter shoulder of the protective sleeve, provided that the protective sleeve has been pushed onto the ferrule according to requirements. Preferably, the protective sleeve is detachably connected to the ferrule by means of a screw connection. For this purpose, the ferrule can have an external thread section and the protective sleeve can have an internal thread section, which can be screwed to one another. The internal thread section of the protective sleeve can be produced easily and economically, for example, by means of a screw tap and the external thread section of the ferrule can be produced easily and economically by means of an automatic lathe. By means of a latching connection and / or a screw connection, a form-fitting reception of the protective sleeve and the ferrule can take place.The ferrule can have a radially protruding diameter shoulder which limits an axial displacement path of the protective sleeve. The ferrule advantageously forms a receiving sleeve for the protective sleeve, onto which the protective sleeve can be pushed in the axial direction. The protruding diameter shoulder formed on the ferrule can form a stop for the protective sleeve and thereby limit the displacement travel of the protective sleeve. Since the protective sleeve is pushed out of the connecting end of the optical fiber close to the end of the ferrule, the radially protruding diameter shoulder of the ferrule limits the axial displacement travel of the protective sleeve in the direction of the end of the ferrule facing away from the connecting end of the fiber. The protective sleeve is then preferably received on the ferrule in a form-fitting manner. It is then also no longer necessary to perform a special fastening of the protective sleeve on the ferrule with regard to displaceability or to provide further components.The protective sleeve can be hollow-cylindrical. The connecting end of the optical fiber is then arranged within the protective sleeve, wherein preferably the longitudinal axis of the optical fiber and the longitudinal axis of the protective sleeve or the rotational axis of the protective sleeve coincide, whereby the protective sleeve and the optical fiber are centered with respect to each other. Due to the hollow cylindrical design of the protective sleeve, the connecting end of the optical fiber is free inside the protective sleeve and is accessible for connection to a further optical fiber. In addition, the connecting end of the optical fiber is protected within the protective sleeve. The outer periphery of the hollow cylindrical protective sleeve can serve for the alignment of two plug connectors with respect to one another or for the alignment of plug connector and socket with respect to one another, wherein an accurate, axis-aligned arrangement is made possible. According to a preferred embodiment, the protective sleeve can have a fiber on the end of the protective sleeve facing away from the ferrule for easy insertion into a further plug connector or a socket on the outer circumference.The optical fiber can be guided in contactless fashion within the protective sleeve. Within the scope of the invention, the term "contactless guidance within the protective sleeve" means that the walls which run parallel to the longitudinal axis or axis of rotation of the profiled sleeve and thus parallel to the extension of the optical fiber do not touch the optical fiber. In other words, the optical fiber is free in contactless fashion within the protective sleeve. The optical fiber thus has no contact with the protective sleeve and is guided through the through bore in the ferrule. This allows simple guidance of the plug connector through the protective sleeve during the connection to a further plug connector or a socket. The contactless guidance of the optical fiber within the protective sleeve also makes it possible to avoid damage to the optical fiber due to heat generation and a resulting burn-up of unsuitable materials.The plug connector can have a fastening sleeve with a through opening at an end of the ferrule facing away from the connecting end of the optical fiber for receiving and fastening the optical fiber and / or the optical fiber. The optical fiber or the optical waveguide can be glued into the through-opening of the fastening sleeve by means of adhesive material for fastening within the fastening sleeve. The through-opening is preferably designed as a through-bore. The fastening sleeve can be inserted into the ferrule and secured within the ferrule by means of a positive and / or force fit. It is also conceivable for the fastening sleeve to be adhesively bonded into the ferrule. According to a preferred embodiment, the ferrule has an internal thread section and the fastening sleeve has an external thread section, which can be screwed to one another. As a result, no further components are required for connecting the ferrule to the fastening sleeve. Because no adhesive material is required for the screw connection, no adhesive material can enter the ferrule either, thereby enabling a transmission of large amounts of light or high powers while at the same time being produced cost-effective. The internal thread section of the ferrule can be produced easily and economically, for example, by means of a screw tap and the external thread section of the fastening sleeve can be produced easily and economically by means of an automatic lathe. Particular requirements for accuracy are not to be taken into account here, since a screw thread formed in this way serves merely for fastening and the actual positioning of the connecting end of the optical fiber in the through-opening of the ferrule takes place.The optical waveguide can be fixed by means of a collet chuck, in particular within the fastening sleeve. The collet has a through bore and a conical slotted region, wherein the optical fiber and / or the optical waveguide are inserted into the collet at the end facing away from the ferrule and at least the optical fiber exits from the slotted region of the collet and is inserted into the ferrule from there. Advantageously, the fastening sleeve can form the collet receptacle by recessing an inner cone matching the collet at the end of the fastening sleeve facing away from the ferrule. The collet can be inserted into this inner conical recess of the fastening sleeve, whereby the through bore of the collet is uniformly compressed in the slotted region of the collet and thus the optical fiber and / or the optical waveguide is held firmly in a force-fitting manner. Thus, in addition to the fastening sleeve, only one further collet is necessary, since the fastening sleeve forms the collet receptacle necessary for clamping the optical fiber. It is conceivable that the collet may be screwed into the fastening sleeve. Preferably, the through bore of the collet, the through opening of the fastening sleeve and the through opening of the ferrule are aligned. In other words, the longitudinal axes of the collet, the fastening sleeve and the ferrule coincide. It is also conceivable that the collet chuck is fastened directly in an inner conical recess of the ferrule, without the fastening sleeve.The connector has an abutment portion which may be formed by a connection portion of the ferrule or the protective sleeve. The contact section of the plug connector is, within the scope of the invention, the section of the plug connector which interacts with a further plug connector or a socket within the scope of a connection. Preferably, the contact portion is the portion of the plug connector which is inserted into the further plug connector or a socket and the outer surface of which serves to guide the plug connector during insertion and comes to contact the further plug connector or the socket. In particular, the contact section of the plug connector is formed by the connecting section of the ferrule, wherein the connecting section of the ferrule has a larger outer diameter than the protective sleeve and / or the receiving sleeve of the ferrule.If the ferrule does not have a connecting section, the protective sleeve can form the contact section of the plug connector in that the receiving sleeve and the protective sleeve arranged thereon preferably extend into the locking sleeve. In other words, a protruding diameter shoulder is formed between the protective sleeve and the connecting section of the ferrule, provided that the connecting section of the ferrule forms the contact section of the plug connector. The contact section of the plug connector preferably extends into a locking sleeve. This means that, if the protective sleeve forms the contact section of the plug connector, the protective sleeve is located in the front region of the ferrule and / or the protective sleeve extends as far as into the locking sleeve.The ferrule can be formed in multiple parts, in particular in two parts. The connection of the plurality of parts of the ferrule can be effected by means of a screw connection. The ferrule is preferably formed in two parts, wherein the second part of the ferrule remote from the protective sleeve, namely the screw-in sleeve, can be screwed into the first part, namely the plug sleeve, on which the protective sleeve is arranged. It is conceivable that the securing ring is formed integrally with the second part of the ferrule remote from the protective sleeve, so that during the assembly or production of the plug connector, the introduction of a diameter shoulder and the insertion of a securing ring into this diameter shoulder can be dispensed with.In order to fix the insertion depth of the fastening sleeve into the ferrule, a counter nut can be screwed onto a first external thread section of the fastening sleeve, wherein the counter nut can be brought to bear on the end face of the ferrule facing away from the connecting end of the optical fiber. The fastening sleeve can first be introduced into the ferrule, for example by screwing in or pushing in, and can then be fixed in its position by end-face placement of the counter nut on the ferrule.The plug connector can have a bayonet connection for connecting and locking the plug connector to a further plug connector or a socket. The plug connector can additionally or alternatively have a locking sleeve which is radially rotatable and axially displaceable relative to the ferrule for connecting and locking the plug connector to a further plug connector or a socket. The locking sleeve can be designed, for example, in the manner of a union nut with a thread or also with a so-called bayonet lock or an alternative type of fastening. It is advantageous if the ferrule has a section which forms a guide sleeve for the locking sleeve. The locking sleeve can then be displaced in the longitudinal direction of the ferrule on this section of the ferrule. Furthermore, a protruding diameter shoulder can be formed on the ferrule or the guide sleeve formed thereon, which diameter shoulder can limit a displacement travel of the locking sleeve in the direction toward the connecting end of the optical fiber. It is also conceivable for the fastening sleeve to have a radially protruding diameter shoulder which limits an axial displacement path of the locking sleeve. In particular, the axial displacement path of the locking sleeve in the direction of the end of the ferrule facing away from the connecting end of the optical fiber can be limited. The locking sleeve can then be received on the ferrule in a form-fitting manner. It is then also no longer necessary to perform a special fastening of the locking sleeve on the ferrule with regard to displaceability or to provide further components.The ferrule can have a radial recess on the diameter shoulder, into which a securing ring of the plug connector can be inserted, which limits the axial displacement path of the locking sleeve. In particular, if the fastening sleeve does not have a radially protruding diameter shoulder, this can be formed simply by latching the securing ring in the radially recessed diameter shoulder. The locking sleeve can then be pushed over the ferrule first and fastened on the ferrule in a positive-locking and axially displaceable manner by means of the securing ring. In particular, the securing ring can be used to limit the axial displacement travel of the locking sleeve in the direction of the end of the ferrule facing away from the connecting end of the optical fiber.On the outer periphery of the ferrule and / or within the locking sleeve, an anti-rotation device can be arranged, which can in particular comprise a latching nose and / or a recess. An O-ring can be arranged and fixed between two diameter shoulders of the ferrule, which form a recess, for sealing with respect to a bushing or the like. The anti-rotation device serves to secure the plug connector, in particular after a connection to a further plug connector or a socket has been produced, against undesired rotation and thus protects the plug connector and / or the optical waveguide configuration from damage.The plug connector can have a coarse thread and a fine thread for adjusting the optical fiber. For rapid introduction and rough positioning of the optical fiber, the optical fiber can first be pushed through the ferrule by means of the rough thread. Subsequently, the fine positioning can be effected by means of the fine thread. Within the scope of the invention, the fine thread has a smaller pitch and / or a narrower thread profile relative to the coarse thread. The plug connector preferably has an adjustment sleeve. The adjustment sleeve can have the coarse thread, which is preferably designed as an external thread, via which the adjustment sleeve can be screwed into the ferrule in an internal thread of the ferrule of complementary design. At the end opposite the coarse thread, the adjusting sleeve can have the fine thread, which is preferably designed as an internal thread, into which the fastening sleeve can be screwed via a complementary external thread of the fastening sleeve. It is alternatively possible for the fastening sleeve to be screwable into the adjusting sleeve via the coarse thread and for the adjusting sleeve to be screwable into the ferrule via the fine thread. Both the adjusting sleeve and the fastening sleeve can be secured by means of a respective lock nut.The optical waveguide configuration comprises a plug connector according to the invention and an optical waveguide fastened thereto. The optical waveguide and / or the optical fiber of the optical waveguide can be introduced into the end of the ferrule facing away from the protective sleeve and can be guided through the ferrule, so that the optical fiber ends in a free-standing manner within the protective sleeve and can be used for connection to a further plug connector or a socket. For polishing the connecting end of the optical fiber, the protective sleeve can be detached from the ferrule and subsequently be arranged again on the ferrule. Thus, for forming the optical waveguide configuration and in particular for polishing the connection end of the optical fiber, neither a polishing wax, which may leave residues on the optical fiber, nor further aids or components, which would have to be disposed of after the polishing process, are necessary. It is conceivable that the optical waveguide and / or the optical fiber is fastened to the fastening sleeve by means of adhesive material. Adhesive material can be used for this purpose, since the fastening sleeve is not located in the connecting region of the plug connector.The optical waveguide can be accommodated in a corrugated tube, wherein the corrugated tube is fastened to an end of the ferrule facing away from the connecting end of the optical fiber. The corrugated tube can be fastened to the ferrule via a corrugated tube sleeve. The corrugated tube sleeve can be fastened to the ferrule by means of screwing, pressing, for example crimping, or adhesive bonding. Additionally or alternatively, the corrugated hose sleeve can be secured to the ferrule by at least one radially insertable grub screw. In order to gain access to the fastening sleeve, for example for adjusting the position of the connecting end of the optical fiber, it may be necessary, depending on the design of the corrugated tube sleeve, to adjust the connecting end of the optical fiber or to reach the fastening sleeve and to vary the insertion depth thereof into the ferrule, push the corrugated tube sleeve back and compress the corrugated tube. However, this is only possible provided that the corrugated hose is correspondingly flexible and can be compressed along its longitudinal extension. If no compression of the corrugated hose is possible, the corrugated hose sleeve can be designed in such a way that it can be pushed over the corrugated hose in the axial direction and thereby releases the fastening sleeve. For this purpose, the corrugated hose sleeve can have an inner diameter which is slightly smaller, equal and / or slightly larger than the outer diameter of the corrugated hose.In a further aspect, the invention relates to a method for producing an optical waveguide configuration having an optical fiber and a plug connector which has at least one ferrule and a protective sleeve, having the following steps: a) introducing the optical fiber into the plug connector, preferably until the connecting end of the optical fiber protrudes from the ferrule at the end of the ferrule close to the optical fiber or terminates flush with the end of the ferrule close to the optical fiber; b) polishing the optical fiber; c) arranging the protective sleeve at the end of the ferrule close to the connecting end of the optical fiber; and d) adjusting the optical fiber.According to the method according to the invention, the optical fiber is first introduced into the ferrule of the plug connector, for example by means of a fastening sleeve, so that the optical fiber passes completely through the ferrule and the connecting end of the optical fiber protrudes minimally from the end of the ferrule which is used for connection to a further plug connector or a socket, or ends flush with the end of the ferrule close to the optical fiber, i.e. the end face or end face of the ferrule. The optical fiber preferably protrudes at most 0.5 mm from the ferrule at the end of the ferrule near the optical fiber. In the subsequent step, the plug connector can be polished by polishing removal of the optical fiber. Here, for example, the end of the ferrule from which the connecting end of the optical fiber minimally protrudes may serve as a holding means of the fiber and / or a stopper for a polishing agent. If the optical fiber of the plug connector has been polished according to requirements, the protective sleeve can be arranged on the ferrule in the subsequent step. For example, the protective sleeve can be screwed or pushed onto the ferrule. After the protective sleeve has been attached, the optical fiber can be adjusted by inserting the polished connecting end of the optical fiber into the protective sleeve and thus standing freely in the protective sleeve due to the design of the protective sleeve. The optical fiber is preferably adjusted by inserting the connecting end of the optical fiber into the protective sleeve until the connecting end of the optical fiber is aligned in alignment with the end face of the protective sleeve facing away from the ferrule. In other words, the protective sleeve and the optical fiber terminate flush.Before step a) of the method according to the invention, i.e. before the optical fiber is inserted into the plug connector, the method can comprise a step a 0). According to step a0), the optical fiber is glued into a fastening sleeve before step a). After the optical fiber has been adhesively bonded into the fastening sleeve, the fastening sleeve can be screwed or pushed into the ferrule in order to introduce the optical fiber.It is conceivable that the plug connector with the protective sleeve already mounted, i.e. that the protective sleeve is already arranged on the ferrule, is made available to a user. Therefore, it is conceivable that before the step b), that is, before polishing the optical fiber, the protective sleeve can be removed from the ferrule. Due to the detachable connection between ferrule and protective sleeve, this is possible in a low-complexity manner.Further advantageous embodiments of the method result from the feature descriptions of the claims directed to the plug connector and the optical waveguide configuration.Preferred embodiments of the invention are explained in more detail below with reference to the appended drawings.The following are shown: FIG. 1 shows an optical waveguide configuration according to the invention with a plug connector according to a first embodiment in a side view; FIG. 2 shows the optical waveguide configuration according to FIG. 1 in a sectional view along the section line A-A; FIG. 3 shows a second embodiment of an optical waveguide configuration according to the invention in a side view; FIG. 4 shows the optical waveguide configuration according to FIG. 3 in a sectional view cut along the section line A-A; FIG. 5 shows a third embodiment of an optical waveguide configuration according to the invention in a side view; FIG. 6 shows the optical waveguide configuration according to FIG. 5 in a sectional view cut along the section line A-A; FIG. 7 shows a fourth embodiment of an optical waveguide configuration according to the invention in a side view; FIG. 8 shows the optical waveguide configuration according to FIG. 7 in a sectional view cut along the section line A-A; FIG. 9 shows a first embodiment of an optical waveguide configuration according to the invention with a corrugated hose; FIG. 10 shows the optical waveguide configuration according to FIG. 9 in a sectional view cut along the section line A-A; FIG. 11 shows a second embodiment of an optical waveguide configuration according to the invention with a corrugated tube in a side view; FIG. 12 shows the optical waveguide configuration according to FIG. 11 in a sectional view cut along the section line A-A; and FIG. 13 shows a further embodiment of an optical waveguide configuration according to the invention in a side view; FIG. 14 shows the optical waveguide configuration according to FIG. 13 in a sectional view cut along the section line A-A; FIG. 15 shows the method according to the invention with steps a0 to d.FIGS. 1 and 2 show, in combination, a first embodiment of an optical waveguide configuration 60 comprising a plug connector 10 and an optical waveguide 20 fastened thereto. A through-opening 12, which is designed as a through-bore, is provided in the ferrule 14 for receiving and positioning a connecting end 16 of the optical fiber 18 of the optical fiber 20. A protective sheath 54 of the optical fiber 20 has been removed from the connecting end 16 of the optical fiber 18. The fastening sleeve 30 is formed with a further through-opening 32 of the fastening sleeve 30, which is formed as a bore and within which the protective sleeve 54 of the optical waveguide 20 and thus the optical waveguide 20 itself is fastened. The fastening sleeve 30 is screwed with its external thread section into the internal thread section of the ferrule. By means of the lock nut 40, which can be brought to bear against the end 28 of the ferrule 14 remote from the connecting end 16 of the optical fiber 18, an adjustment and fixing of the insertion depth of the fastening sleeve 30 into the ferrule 14 is possible. A securing ring 50 is arranged in a recessed diameter shoulder of the ferrule 14, which ring delimits an axial displacement path of the locking sleeve 44 on the ferrule 14. Furthermore, the ferrule 14 has a radially protruding diameter shoulder 26 for limiting the axial displacement path of the locking sleeve 44 in the opposite direction. The locking sleeve 44 is thus displaceable between the securing ring 50 and the radially protruding diameter shoulder 26 in the axial direction of the plug connector 10 and is rotatable about the ferrule 14. In order to prevent undesired rotation of the plug connector 10, in particular in a connection configuration, i.e. when the plug connector 10 has received a connection with a further plug connector or a socket, an O-ring 46 is fixed between two diameter shoulders of the ferrule 14 for sealing purposes. If the plug connector 10 is inserted into a socket or into a further plug connector, the O-ring 46 comes to rest against this further plug connector or the socket and prevents an undesired rotation of the plug connector 10. For this purpose, the protective sleeve 22 engages around the receiving sleeve 72 of the ferrule 14. That is, the protective sleeve 22 does not have direct contact with the connecting end 16 of the optical fiber 18. It is furthermore apparent from FIG. 2 that the connecting end 16 of the optical fiber 18 terminates flush with the protective sleeve 22 or can be positioned in a defined manner. It is furthermore apparent from FIG. 2 that the connecting section 36 of the ferrule 14 forms the contact section 38 of the plug connector 10. The contact portion 38 of the plug connector 10 comes to bear against the socket or the further plug connector when the plug connector 10 is connected to a socket or a further plug connector. Between protective sleeve 22 and connecting section 36 of ferrule 14, a protruding diameter shoulder is formed. That is, the ferrule according to the first embodiment of an optical waveguide configuration 60 has a larger outer diameter than the protective sleeve 22 in the region of the connecting section 36 of the ferrule 14.A second embodiment of an optical waveguide configuration 60 according to the invention can be seen from a combination of FIGS. 3 and 4. In order to avoid repetitions, only the differences from the first embodiment of an optical waveguide configuration 60 shown with FIGS. 1 and 2 will be discussed below. In contrast to the optical waveguide configuration 60 from FIGS. 1 and 2, the optical waveguide 20 and its optical fiber 18 are accommodated and secured in a collet 34, in particular in its through-bore 52. As soon as the collet 34 with the optical waveguide 20 is completely inserted or screwed into the conical recess of the fastening sleeve 30, clamping of the optical waveguide 20 and / or the optical fiber 18 takes place within the collet, whereby the optical fiber is fixed in the fastening sleeve 30. In addition, in contrast to the optical waveguide configuration 60 according to FIGS. 1 and 2, no securing ring 50 is provided on the ferrule. To limit the axial displacement path, in addition to the protruding diameter shoulder 26 on the ferrule, the outer diameter of the counter nut 40 is designed to be larger than the outer diameter of the ferrule at the end 28 of the ferrule 14 on which the counter nut 40 can be brought to rest.A combination of FIGS. 5 and 6 reveals a further embodiment of an optical waveguide configuration 60 according to the invention. In contrast to the first embodiment of an optical waveguide configuration 60 according to the invention, which is illustrated in FIGS. 1 and 2, the ferrule 14 is formed in two parts according to FIGS. 5 and 6. The second part of the ferrule 14, namely the screw-in sleeve 56, which is designed to receive the fastening sleeve 30, can be screwed by means of an external thread into an internal thread of the first part of the ferrule 14, namely into the plug sleeve 58. Plug sleeve 58 and screw-in sleeve 56 of ferrule 14 have a continuous through-opening 12, through which optical fiber 18 is guided. The protruding diameter shoulder 66 of the screw-in sleeve 56 delimits, on the one hand, the insertion path of the screw-in sleeve 56 into the plug sleeve 58 of the ferrule 14 and simultaneously serves to delimit the axial displacement path of the locking sleeve 44.FIGS. 7 and 8 show, together, a fourth embodiment of an optical waveguide configuration 60 according to the invention, in which, in contrast to the optical waveguide configuration 60 from FIGS. 1 and 2, the protective sleeve 22 forms the contact portion 38 of the plug connector 10. For this purpose, the protective sleeve 22 and the receiving sleeve 72 extend into the locking sleeve 44 or only in the front part of the ferrule. Thus, when a plug connection is formed with a further plug connector or a socket, the protective sleeve 22 interacts with the further plug connector or the socket and not, as in FIGS. 1 and 2, the connecting section 36 of the ferrule 14.FIGS. 9 and 10 show, in combination, a further embodiment of an optical waveguide configuration 60, in which the optical waveguide 20 is surrounded by a corrugated tube 62. For connecting corrugated tube 62 and ferrule 14, a corrugated tube sleeve 64 is arranged on ferrule 14, which can be secured through radial bore 68 on ferrule 14 by means of a grub screw, not shown here.The corrugated hose can be fastened to the corrugated hose sleeve by adhering or by pressing the corrugated hose sleeve in a clamping manner or by screws that can be introduced laterally and / or radially. The corrugated hose 62 can be connected to the corrugated hose sleeve 64 at the end of the corrugated hose sleeve 64 facing away from the ferrule 14. For adjusting the optical fiber 18 by adjusting the insertion depth of the fastening sleeve 30 into the ferrule 14, the corrugated tube sleeve 64 can be pushed back in order to release the fastening sleeve 30. For this purpose, however, compression of the corrugated hose 62 is necessary.FIGS. 11 and 12 show a further embodiment of an optical waveguide configuration 60 according to the invention with a corrugated tube 62, wherein, in contrast to the embodiment according to FIGS. 9 and 10, no compression of the corrugated tube 62 is necessary in order to carry out an adjustment of the fastening sleeve 30. This is because the corrugated hose sleeve 64 is designed such that it can be pushed back over the corrugated hose 62 in order to expose the fastening sleeve 30. For this purpose, the section of the ferrule 14 on which the corrugated tube sleeve 64 is arranged has an outer diameter which substantially corresponds to the outer diameter of the corrugated tube 62. In addition, the protruding diameter shoulder 66 of the screw-in sleeve 56 of the ferrule 14 can limit the axial displacement path of the locking sleeve 44 on one side and limit the displacement path or the displacement path of the corrugated hose sleeve 64 on the other side. Again, the corrugated tube can be fastened to the corrugated tube sleeve by adhering or by pressing the corrugated tube sleeve in a clamping manner or by screws that can be introduced laterally and / or radially.FIGS. 13 and 14 show a further embodiment of an optical waveguide configuration 60 according to the invention. The plug connector 10 can have a coarse thread 74 and a fine thread 76 for adjusting the optical fiber. For rapid introduction and rough positioning of the optical fiber, the optical fiber can first be pushed through the ferrule 14 by means of the rough thread 74. Subsequently, the fine positioning can be effected by means of the fine thread 78. The coarse thread 74 and the fine thread 76 are formed on the adjusting sleeve 78. The adjustment sleeve 78 can be screwed into the ferrule 14 via the coarse thread 74, which is designed as an external thread. At the end of the adjusting sleeve 78 opposite the coarse thread 74, the fine thread 74 is designed as an internal thread. By means of the fine thread, the fastening sleeve 30 can be screwed into the adjusting sleeve 78 via its external thread section 42. Both the adjusting sleeve and the fastening sleeve are secured by means of a respective counter nut 40.FIG. 15 shows steps a0) to d) of the method according to the invention for producing an optical waveguide configuration 60. In step a 0), as shown in FIG. 13 a 0), the optical waveguide 20 is introduced into the fastening sleeve 30 and the optical fiber 18 is glued or clamped. In the subsequent step a), the fastening sleeve 30 is arranged together with the optical fiber 18 within the ferrule 14, wherein the fiber 18 is guided axially through the ferrule 14 and protrudes minimally at the end 24 of the ferrule 14 or ends flush with the end 24 of the ferrule 14. After polishing the plug connector 10 or the optical fiber 18, the optical fiber 18 initially ends flush with the end 24 of the ferrule 14 and has been positioned in a defined manner, as shown in FIG. 13 b). According to FIG. 13 c) and step c) of the method according to the invention, protective sleeve 22 is subsequently arranged at end 24 of ferrule 14. The adjustment of the optical fiber 18 according to step d) of the method according to the invention is effected by displacing the fastening sleeve 30 within the ferrule 14, as a result of which the optical fiber 18 can be pushed out of the ferrule 14 at the end 24. If the optical fiber 18 has been transferred into the desired position, as shown in FIG. 13 d), preferably flush with the end face of the protective sleeve 22 or at a defined position, the position of the fastening sleeve 30 can be secured by the lock nut 40. The optical waveguide configuration 60 provided in this way, as is illustrated in FIG. 13 d), can be used for connection to a further plug connector or a socket which is not prone to errors and is free of damage. In particular, because no further auxiliary agents or auxiliary agents that could remain on the optical fiber 18 are necessary for polishing the optical fiber 18, burning of the optical fiber 18 due to thermal loads can be effectively prevented. In addition, due to the detachable design of the protective sleeve 22, the protective sleeve 22 can be removed during the polishing process, whereby the fiber 18 becomes easily accessible and, in addition, can be held securely for polishing at the end 24 of the ferrule 14, whereby the polishing process is not made more difficult or impaired by undesired oscillations of the optical fiber 18.

Claims

Plug connector (10) for the detachable connection of optical waveguides (20), wherein the plug connector (10) comprises a ferrule (14) formed with a through-opening (12) for receiving and positioning a connection end (16) of an optical fiber (18) of an optical waveguide (20), characterized in that the plug connector (10) has a protective sleeve (22) which can be connected to the end (24) of the ferrule (14) close to the connection end (16) of the optical fiber (18).Plug connector according to Claim 1, characterized in that the protective sleeve (22) can be detachably connected to the ferrule (14) by means of a latching connection and / or screw connection.Plug connector according to Claim 1 or 2, characterized in that the ferrule (14) has a radially projecting diameter shoulder (70) which delimits an axial displacement path of the protective sleeve (22).Plug connector according to one of Claims 1 to 3, characterized in that the protective sleeve (22) is of hollow cylindrical design.Plug connector according to one of Claims 1 to 4, characterized in that the optical fibre (18) is guided in contactless fashion within the protective sleeve (22).Plug connector according to one of Claims 1 to 5, characterized in that the plug connector (10) has, on an end (28) of the ferrule (14) facing away from the connection end (16), a fastening sleeve (30) having a through-opening (32) for receiving and fastening the optical waveguide (20) and / or the optical fiber (18).Plug connector according to Claim 6, characterized in that an optical waveguide (20), in particular the optical fibre (18), is fixed by means of a collet chuck (34).Plug connector according to one of Claims 1 to 7, characterized in that a connecting section (36) of the ferrule (14) or the protective sleeve (22) forms the bearing section (38) of the plug connector (10).Plug connector according to one of Claims 1 to 8, characterized in that the ferrule (14) is formed in multiple parts, in particular in two parts.Plug connector according to one of the preceding claims, characterized in that a counter nut (40) is screwed onto a first external thread section (42) of the fastening sleeve (30), wherein the counter nut (40) can be brought to bear on the end face on the end (28) of the ferrule (14) facing away from the connecting end (16) of the optical fibre (18).Plug connector according to one of the preceding claims, characterized in that, for the connection and locking of the plug connector (10) to a further plug connector or a socket, the plug connector (10) has a locking sleeve (44), which is radially rotatable relative to the ferrule (14) and axially displaceable, or a bayonet lock.Plug connector according to one of the preceding claims, characterized in that a rotation prevention means is arranged on the outer periphery of the ferrule (14) and / or within the locking sleeve (44).Plug connector according to one of Claims 1 to 12, characterized in that the ferrule (14) has a radially recessed diameter shoulder (48), into which a securing ring (50) is inserted, which delimits an axial displacement path of the locking sleeve (44).Plug connector according to one of Claims 1 to 13, characterized in that the plug connector (10) has a coarse thread (74) and a fine thread (76) for adjusting the optical fibre (18).An optical fibre configuration (60) comprising a connector (10) according to any preceding claim and an optical fibre (20) attached thereto.Optical waveguide configuration (60) according to Claim 15, characterized in that the optical waveguide (20) is accommodated in a corrugated tube (62), the corrugated tube (62) being fastened to an end (28) of the ferrule (14) facing away from the connecting end (16) of the optical fiber (18).Method for producing an optical waveguide configuration (60) having an optical fiber (18) and a plug connector (10) which has at least one ferrule (14) and a protective sleeve (22), having the steps of a) introducing the optical fiber (18) into the plug connector (10), preferably until the connecting end (16) of the optical fiber (18) protrudes from the ferrule (14) at the end (24) of the ferrule (14) which is close to the optical fiber (18) or terminates flush with the end of the ferrule which is close to the optical fiber; b) arranging the protective sleeve (22) at the end (24) of the ferrule (14) which is close to the connecting end (16) of the optical fiber (18); and d) adjusting the optical fiber (18).The method of manufacturing an optical fiber configuration according to claim 17, wherein prior to step a), the following step a0) is comprised: a0) adhering the optical fiber (18) into a fixing sleeve (30).The method for manufacturing an optical fiber configuration according to claim 17 or 18, wherein before step b), the following step b0) is comprised: b0) removing the protective sleeve (22) from the ferrule (14).

Images