Optical fiber connector

Abstract

The present disclosure relates to an optical fiber connector (1) comprising: a tubular rear base element (5) extending from a rear end (4) to a front end (5) in a longitudinal direction (x) and comprising an optical fiber deflection section (6) on the inside, the optical fiber deflection section is configured to provide a deflection space for at least one laterally deflected optical fiber (8) extending across the tubular rear base element (5) in the installed position of the optical fiber connector (1); a tubular front base element (9) comprising, at the rear end (10) thereof, a recess (12) in which the front section (13) of the tubular rear base element (5) is arranged in a form-fitting manner; and a ferrule (14) arranged to be deflectable against the force of a spring (15) in a ferrule holder (16) arranged inside the tubular front base element (9), in front of the tubular rear base element (5).

Description

Technical Field

[0001] The present disclosure relates to a fiber optic connector having an improved multi-part design suitable for extending cable length. Background Art

[0002] EP2142951A1 published by the present applicant on January 13, 2010 relates to an optical connector, particularly for external use, for detachably frontally connecting to at least two optical cables along the connector axis. The optical connector comprises a socket part and a plug part, parts of which are substantially cylindrical in design with respect to the connector axis, can be detachably plugged into each other along the connector axis and can be locked in the plugged state. For the purpose of rapid locking, a locking mechanism is provided, which is equipped with a latching function and automatically latches during insertion.

[0003] US2012257859A1, published by Nhep Ponharith on October 11, 2012, relates to a connector comprising a ferrule assembly having a ferrule, a hub and a spring. The ferrule has a distal side accessible at the distal end of the connector housing, wherein the ferrule can move in a proximal direction relative to the connector housing. The distal position and the proximal position are separated by an axial displacement distance. The proximal movement of the ferrule resists the bias of the spring. The cable of the assembly includes an optical fiber contained in a sheath, and also includes a tension layer between the optical fiber and the sheath, which is anchored to the connector housing. The optical fiber extends from the proximal end of the connector housing through a fiber channel to the ferrule. The optical fiber has a distal portion encapsulated in the ferrule. The fiber channel has a fiber take-up region, which is configured to shorten the excess length of the optical fiber corresponding to the axial displacement of the ferrule. Summary of the invention

[0004] When, for example, the optical cable assembly is coiled / unwound, the internal parts of the cable, such as at least one optical fiber and the surrounding tube (so-called empty tube) in which the at least one optical fiber is arranged, may be displaced relative to the end of the optical cable in an undesirable manner. The same applies when the cable is subjected to axial loads. This may cause problems because the at least one optical fiber and the tube may be pushed into or pulled out of the optical fiber connector in an undesirable manner. When being pushed into the optical fiber connector, bending, kinking or even fiber breakage may occur. Vice versa, when tension is applied to the optical cable, the at least one optical fiber may be pulled out of the optical fiber connector. As a result, the ferrule is pulled back and may lose contact with the mating ferrule. In severe cases, the at least one optical fiber may be damaged due to excessive tension.

[0005] In order to avoid unwanted movement of at least one optical fiber relative to the fiber optic connector to which it is attached, the inner cable components and the cable jacket are usually firmly bonded together with a low viscosity adhesive that penetrates the strain relief element (glass roving or aramid) that forms part of the optical cable. A problem with such an arrangement is that the fiber over-length (either too short or too long) within the fiber optic connector, caused by, for example, manufacturing tolerances of the ferrule length, the fiber length, or the connector housing components, cannot be easily controlled or compensated. In particular, inappropriate fiber over-length may lead to fiber kinking when the fiber optic connector is coupled or pulling on the fiber when the fiber optic connector is released, thereby causing signal loss or even fiber breakage.

[0006] It can be seen that one of the problems to be solved is to provide an assembly-friendly fiber optic connector, thereby allowing adjustment of the optical fiber excess length within the fiber optic connector during assembly.

[0007] The fiber optic connector according to the present disclosure and as described below provides the possibility of overcoming this problem. The fiber optic connector provides the possibility of efficiently adjusting different fiber lengths in the fiber optic connector during the assembly process. In addition, considering the small size and short fiber length, it is desirable to design the fiber optic connector in a way that an efficient assembly process can be achieved. Therefore, the fiber optic connector according to the present disclosure generally includes a tubular base element, which extends from the rear end portion of the fiber optic connector to the front end portion in the longitudinal direction. The fiber optic connector also includes a ferrule, which is arranged to overcome the force deflection of a spring in a ferrule holder, and the ferrule holder is arranged adjacent to the front end portion of the tubular base element. In addition, the ferrule holder is arranged with a ferrule to terminate at least one optical fiber.

[0008] Fiber optic connectors according to the present disclosure are intended for applications connected to long cables (length > 50 meters) or where axial loads occur (e.g., hanging cables). Such situations often occur at cellular base station facilities, mining facilities, and broadcast facilities, where cable assemblies are often coiled and unwound, and / or fiber movement due to longitudinal environmental stresses (e.g., contraction and expansion of antenna towers) is common. In order to connect a fiber optic connector to, for example, a mating fiber optic connector or a base station, the fiber optic connector generally includes a plug element.

[0009] Especially for outdoor applications, a robust, easy to assemble and reliable fiber optic connector is desired, which can withstand harsh environmental influences. Depending on the size and available assembly space, the tubular base element can be either made as a single part or as a multi-part base element. When the tubular base element of the fiber optic connector is assembled from a tubular rear base element and a tubular front base element connected thereto (as described below), good results with respect to an assembly-friendly and robust design can be achieved. In the case of a multi-part design with a tubular rear base element and a tubular front base element, the rear end of the tubular rear base element is usually the rear end of the entire tubular base element at the same time. Accordingly, the front end of the tubular front base element is usually also the front end of the entire tubular base element at the same time.

[0010] The tubular rear base element typically comprises, on its inner side, a fiber deflection section in the form of a receiving space in which the optical fiber can be fully deflected in a lateral direction. In a variant, the tubular rear base element comprises a first opening at its rear end and a second opening at its front end, the first opening and the second opening being configured to allow at least one optical fiber to extend through the tubular rear base element. The receiving space may have a varying cross-section between the first opening and the second opening, thereby allowing the at least one optical fiber to be deflected.

[0011] When the tubular front base element and the tubular rear base element are connected to each other by a snap connection, a fast and reliable connection and therefore efficient assembly can be achieved. The shoulder can be designed to form an undercut in the longitudinal direction. This undercut can be designed as a circumferential groove, which is formed by the shoulder in the installed state. The tubular front base element usually includes a recess at its rear end, and the front section of the tubular rear base element is arranged in the recess in a form-fitting manner. When the front end of the tubular rear base element is designed as a collar, a good result can be achieved, and the collar corresponds to the recess of the tubular front base element. The collar can be arranged in the tubular front base element in a self-locking (e.g., press fit) manner to avoid the latter from popping out due to the load of the ferrule spring, which is usually within the range of 20 Newtons. The tubular front base element and the tubular rear base element are usually interconnected to each other by a clasp, which is arranged between the relative circumferential shoulders of the tubular front base element and the tubular rear base element. In order to additionally increase the protection against unwanted rotation of the tubular rear base element relative to the tubular front base element, at least one anti-twist element can be arranged at the front end of the tubular rear base element. The anti-twist element usually engages with the recess of the tubular front base element and prevents the tubular rear base element from rotating relative to the tubular front base element.

[0012] Typically, after the tubular rear base element has been assembled so as to surround, for example, a prefabricated cable assembly, a ferrule holder (with a ferrule and a spring arranged therein) may be arranged at the front end of the tubular rear base element. The preassembled unit may form a prefabricated unit comprising the tubular rear base element, the ferrule holder with the ferrule and the spring, and the connecting element. The prefabricated unit is typically connected to the tubular front base element by connecting the front section of the tubular rear base element to the tubular front base element, thereby forming the base element.

[0013] The front section of the tubular rear base element is usually inserted into the recess at the rear end of the tubular front base element together with the ferrule holder. After inserting the tubular rear base element and the ferrule holder, the connecting element can be adjusted in the longitudinal direction to finally determine the free length of at least one optical fiber inside the base element, and then the connecting element is fixed to the tubular rear base element. The interconnected tubular rear base element and the front base element can surround the ferrule holder of the optical fiber connector. The ferrule holder usually includes a ferrule, which is arranged in the ferrule holder and can overcome the force deflection of the spring. The ferrule holder may include a shoulder, which can abut against the shoulder of the tubular rear base element when inserted into the tubular front base element from the rear end. In the installed state, the shoulder of the ferrule holder can be fixed between the shoulder of the tubular rear base element and the groove of the tubular front base element attached thereto.

[0014] In a preferred variation, the fiber optic connector includes a connecting element, preferably by gluing the optical fiber and the hollow tube into a bushing to make it firmly connected to the connecting element. The connecting element is usually arranged at the rear end of the tubular base element, and the connecting element is configured to mechanically attach the optical cable to the tubular base element. During assembly, the connecting element can be arranged in an adjustable manner relative to the tubular base element in the longitudinal direction. Thus, the connecting element is configured to adjust the free length of the optical fiber extending between the connecting element and the ferrule. During assembly, the connecting element (with the optical cable attached thereto) is interconnected to the rear end of the tubular base element, as described below. The connecting element can be arranged inside the rear end of the tubular base element, for example, in a slidable manner in a hole in the tubular base element, and the connecting element is configured to mechanically attach the optical cable to the tubular rear base element.

[0015] The connecting element (e.g., in the form of a bushing or cylindrical sleeve) may include a collar for receiving the end section of the optical cable. The collar may be designed so that it can receive the cable jacket and / or cable braid of the optical cable, while at least one optical fiber extends through the connecting element into the tubular base element. The end section of the optical cable may be attached to the collar by crimping and / or adhesive. The connecting element may typically be either inserted into the rear end of the tubular base element or slid onto the rear end of the tubular base element (or onto the rear end of the tubular rear base element in an alternative variation). This allows the free length of the optical fiber to be adjusted. The connecting element and the tubular base element may be telescopically arranged relative to each other during assembly. Typically, a recess is formed between the connecting element and the tubular base element, the recess being configured to receive adhesive in different longitudinal positions through an inlet for fixing the connecting element. The connecting element may have a through hole for the at least one optical fiber, the through hole may have a smooth inlet and / or a smooth outlet. This allows the at least one optical fiber to be deflected at the outlet of the at least one optical fiber at the connecting element.

[0016] The connecting element (with the optical cable attached thereto) can be adjusted in the longitudinal direction to straighten the optical fiber in the tubular rear base element and thereby adjust the relative length of the optical fiber connector to the free optical fiber length of at least one optical cable. Typically, after assembling the tubular base element, the connecting element is fixed so that the free length of the optical fiber inside the base element is fixed. Typically, the adhesive (e.g., epoxy) is injected through an inlet in the form of a through hole arranged in the tubular rear base element. The hole can be arranged adjacent to the rear end of the tubular rear base element and the recess is filled with adhesive until excess adhesive leaves the ventilation hole usually arranged in the opposite half shell of the tubular rear base element.

[0017] In order to achieve a mechanically stable attachment even under varying axial loads due to thermal expansion and / or creep, a recess can be formed by corresponding grooves in the tubular base element and the connecting element. In a variant, the recess is formed by an annular groove or a thread arranged at the connecting element and / or a notch arranged at the rear end of the tubular base element. In the installed state, a crimping sleeve can attach the connecting element to the tubular base element. If an adhesive is used, the crimping sleeve holds the connecting element in its position until the adhesive in the recess has solidified. This allows the assembly to continue without having to hold the base element in a fixture until the adhesive has cured. If side loads occur in the application, the crimping sleeve can support / reinforce the connecting element and the tubular rear base element.

[0018] When an additional crimping sleeve is installed so as to surround the connecting element, additional stability and sealing of the connection can be achieved. A crimping sleeve can be attached to the tubular base element, which crimping sleeve surrounds the connecting element in the installed state and is crimped to the rear end of the tubular base element and the connecting element. The crimping sleeve can be crimped to the collar of the connecting element and thereby additionally fix the optical cable to the connecting element by the crimping force.

[0019] Due to the crimped-on crimping sleeve, the assembly with the uncured adhesive optionally applied is fixed at once, so that there is no need to pause during the assembly process until the adhesive for holding the cable plug has solidified. This solution avoids squeezing the optical fiber, which can affect the optical performance. The connecting element (having the crimping sleeve installed thereon) is attached to the optical fiber, and the optical cable itself is firmly attached to the connecting element by gluing. In this way, the optical fiber and the empty tube are prevented from being pushed into the optical fiber connector. Depending on the design, the connecting element is only kept by the crimping sleeve, without the need for the connecting element to be glued to the tubular base element. In addition, the crimping sleeve can further improve the structural integrity of the integral connector. The crimping sleeve can especially strengthen the rear end of the tubular base element, which can be particularly advantageous for the dissipation of bending force.

[0020] The ferrule holder is usually arranged inside the tubular base element adjacent to the front end. The ferrule can be arranged inside the ferrule holder together with a spring extending from the shoulder of the tubular base element to the ferrule in the longitudinal direction. When assembling the optical fiber connector.

[0021] Regardless of the design of the tubular base element (single part or multiple parts), in order to prevent the ferrule holder from rotating relative to the longitudinal direction, the ferrule holder may include a protrusion that engages with a recess of the ferrule holder in the installed state or vice versa. The ferrule is usually designed as a mechanical transfer ferrule. The MT ferrule allows passive or active fiber optic connection packaging. At least one optical fiber is usually attached to the ferrule with a fiber optic connector grade heat-cured epoxy resin and can be polished with various commercially available batches of connector polishers. In the installed state, the spring can be arranged adjacent to the front end of the tubular base element and rest against the shoulder of the tubular base element. In order to avoid the ferrule holder from rotating relative to the longitudinal direction, the ferrule holder may include at least one protrusion that interacts with a corresponding recess in the tubular base element. In a variant, the protrusion can be designed as a tongue-shaped piece that engages with a groove of the tubular base element in the installed state. If the tubular base element is a multi-part design, the groove can extend from the rear end of the tubular front base element to the front end. Depending on the design, a fiber optic connector may be configured to interconnect several optical fibers.

[0022] In a variation, the fiber optic connector is designed as a multi-fiber push-on connector (MPO connector). The MPO connector is designed to reduce the amount of time required to fuse individual connectors. In the case of combining several optical fibers in one connector, the MPO connector not only greatly reduces the time to connect the optical fibers, but also saves a lot of space. The MPO ferrule allows the preparation of the fiber tip protrusion and reduces the polishing time and effort, resulting in excellent end face geometry control. MPO ferrules are generally available in 2, 4, 8, 12, 16, 24, 32 and 48 cores.

[0023] The optical fiber connector may include a protective sleeve. The protective sleeve is typically assembled by sliding it from the rear side of the tubular base element onto the tubular base element. The protective sleeve is typically configured to seal the optical cable, at least one optical fiber and the tubular base element from environmental influences and additionally protect the tubular base element from collisions or protect the tubular base element when it falls. Good results can be achieved when the protective sleeve is installed so that it surrounds the tubular connecting element and is attached to the tubular base element by a crimping ring. The crimping ring may be arranged on the outside of the clasp. The protective sleeve is typically made of a soft elastic material and may be incorporated into a cable kink protector at its rear end. The protective sleeve may include a circumferential collar on the inside at its front end, which engages with an annular recess arranged at the tubular front base element in the installed state or vice versa.

[0024] Good results can be achieved when the tubular base element or the tubular rear base element and / or the tubular front base element consists of two half shells interconnected to one another. Preferably, the two half shells are interconnected to one another along a dividing plane extending in the longitudinal direction. For positionally accurate mounting, the half shells can be assembled to one another via a snap connection and / or with pins and corresponding holes, thereby surrounding the free length of at least one optical fiber arranged therein. A good compromise between weight and structural integrity can be achieved when the tubular base element (or in particular the tubular rear base element) comprises ribs reinforcing the outer shell surface.

[0025] The plug element (which is usually arranged at the front end of the tubular base element) can include a locking mechanism with a latch element, which automatically latches during connection. The latch element can be configured to interact and engage with the locking element, for example in the form of a latch lug or a collar. Therefore, the latch element is usually designed as an elastically expandable locking ring, which can be arranged concentrically with respect to the longitudinal direction. In order to achieve a quick locking connection, the plug element may include an actuating element, which includes a locking sleeve, which is arranged concentrically with respect to the longitudinal direction and can be displaced in the longitudinal direction so that the locking ring is unlocked. In a variation, the tubular base element includes a circumferential recess arranged adjacent to the front end, which is configured to receive a latch element for interconnecting the optical fiber connector to the paired optical fiber connector. When pulled by an operator, the locking sleeve interacts with the latch element and retracts the latch element. Furthermore, in order to seal the connection from environmental influences in the mounted state, a seal may be arranged inside the tubular base element so as to surround the ferrule holder, which seal seals the connection from environmental influences in the mounted state.

[0026] A variation of the assembly process for assembling a fiber optic connector body with a multi-part tubular base element and at least one optical fiber is performed as follows:

[0027] Mounting the tubular rear base element around the at least one optical fiber, preferably around a prefabricated cable assembly fixed at the end to the cable, the prefabricated cable assembly having a connecting element and already comprising a spring and a ferrule. The connecting element can be arranged in its forward position so that its front end is arranged adjacent to or inside the optical fiber deflection portion to allow the spring to be released for assembling the tubular front base element.

[0028] • Insert the ferrule together with the tubular rear base member into the tubular front base member.

[0029] - Adjusting the connecting element (which is preferably arranged telescopically relative to the tubular rear base element) in the longitudinal direction so that the free length of the at least one optical fiber inside the tubular rear base element remains straight.

[0030] - Inserting the front section of the tubular rear base element into the recess of the tubular front base element (preferably by means of a press fit) to avoid ejection due to the load of the spring.

[0031] • The tubular rear base member is secured by inserting a snap ring into a groove formed by the tubular front base member and the tubular rear base member.

[0032] - Optionally, adhesive is injected into the recess between the tubular rear base element and the connecting element, for example through the inlet, until excess adhesive exits the outlet, which is preferably arranged opposite the inlet.

[0033] · Place a crimping sleeve over the tubular rear base element and the connecting element. Pull the optical cable to straighten the at least one optical fiber in the tubular rear base element and crimp the crimping sleeve over the tubular rear base element and the connecting element. The crimping sleeve thereby fixes the relative distance of the connecting element to the tubular rear base element. If an adhesive is used, the crimping sleeve may hold the connecting element in its position until the epoxy adhesive in the tubular rear base element has solidified.

[0034] - Optionally, slide a protective sleeve from the optical cable (placed on the protective sleeve prior to assembly) over the rear ends of the tubular rear and front base elements. The protective sleeve may seal the optical cable and base element.

[0035] It will be understood that both the foregoing general description and the following detailed description present embodiments and are intended to provide an overview or framework for understanding the nature and character of the present disclosure. The accompanying drawings are included to provide a further understanding and are incorporated into and constitute a part of this specification. The accompanying drawings illustrate various embodiments and together with the description serve to explain the principles and operation of the disclosed concepts. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The present disclosure will be more fully understood from the detailed description and accompanying drawings given below, which should not be considered to be limited to the disclosure described in the appended claims. The accompanying drawings show:

[0037] Figure 1 A variation of a fiber optic connector is shown in perspective views from the front and above with a partial cut-away opening;

[0038] Figure 2 Shown according to Figure 1 An enlarged detail view of a tubular rear base member and a tubular front base member of a fiber optic connector;

[0039] Figure 3 The exploded perspective view from the front and from above shows the Figure 1 An optical fiber connector having a partial cutout;

[0040] Figure 4 Figure 4a It is shown in Figure 1 The base element of the optical fiber connector and in Figure 4b It is shown in Figure 4a a cross-sectional view of a base element;

[0041] Figure 5 Figure 5a It is shown in Figure 1 Fiber optic connectors and in Figure 5b It is shown in Figure 5a A magnified detail view of a ferrule retainer of a fiber optic connector;

[0042] Figure 6 Figure 6a It is shown in Figure 1 Fiber optic connectors and in Figure 6b It is shown in Figure 6a An enlarged detail view of a connecting element of a fiber optic connector;

[0043] Figure 7 Figure 7a It is shown in Figure 1 Fiber optic connectors and in Figure 7b It is shown in Figure 7a An enlarged detail view of a plug element of a fiber optic connector;

[0044] Figure 8 Figure 8a An alternative variant of the base element of the optical fiber connector is shown in Figure 8b A cross-sectional view of a base element of an alternative variation of a fiber optic connector is shown in FIG. DETAILED DESCRIPTION

[0045] Reference will now be made in detail to certain embodiments, examples of which are illustrated in the accompanying drawings, in which some, but not all, features are shown. Indeed, the embodiments disclosed herein may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; instead, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Whenever possible, like reference numerals will be used to refer to like parts or portions.

[0046] Figures 1 to 3 A variation of an optical fiber connector 1 is shown. The optical fiber connector 1 shown comprises a multi-part tubular base element 2 and a plug element 36 interconnected therewith, which is used to interconnect the optical fiber connector 1 to, for example, a mating optical fiber connector 1. The tubular front base element 9 and the tubular rear base element 5 of the variation shown are connected to each other by a snap connection 18 and fixed to each other in the longitudinal direction x by a snap ring 20, which is arranged between the opposite circumferential shoulders 19 of the tubular front base element 9 and the tubular rear base element 5. The shoulder 19 is designed to form an undercut in the circumferential direction. The undercut is designed as a circumferential groove, which is formed by the shoulder 19 in the installed state. The snap ring 20 shown is arranged in the circumferential groove and thereby mechanically interconnects the tubular front base element 9 and the tubular rear base element 5 to each other in the longitudinal direction x. After the tubular rear base element 5 is interconnected to the tubular front base element 9, the snap ring 20 of the variation shown is inserted into the circumferential groove. To achieve a torsionally rigid design, in particular with respect to bending forces along the longitudinal axis, the recess 12 shown at the rear end 10 of the tubular front base element 9 extends along the longitudinal axis x from the rear end towards the front end 11 of the tubular front base element 9 .

[0047] Figure 2 A tubular rear base element 5 is shown, which forms a fiber deflecting section 6. In the variant shown, the tubular rear base element 5 comprises a first opening 43 arranged at its rear end and a second opening 44 arranged at its front end, the first opening 43 and the second opening 44 being configured to allow at least one optical fiber 8 to pass through the tubular rear base element 5 along the longitudinal axis x. The tubular rear base element 5 may form a receiving space having a varying cross section between the first opening 43 and the second opening 44 in order to enable the at least one deflected optical fiber 8.

[0048] Figure 3 The base element 2 of the optical fiber connector 1 shown is shown, which is assembled from a tubular rear base element 5 and a tubular front base element 9 connected thereto. The tubular rear base element 5 of the variant shown is assembled around at least one optical fiber 8 of free length. The tubular rear base element 5 shown is composed of two half shells 17 interconnected with each other. The two half shells 17 are interconnected with each other along a dividing plane extending along the longitudinal direction x. In order to carry out accurate installation in position, the half shells 17 shown are assembled with each other via a snap connection or with pins, thereby surrounding at least one optical fiber 8 arranged therein. The tubular front base element 9 shown has a connection interface for attaching a plug element 36 to the tubular front base element 9 at its front end 11, and has a connection interface for attaching the tubular rear base element 5 to the tubular front base element 9 at its rear end 10.

[0049] The tubular front base element 9 shown is generally configured to interconnect the plug element 36 to the tubular rear base element 5 and to accommodate the ferrule holder 16, which is arranged inside the tubular front base element 9 and in front of the tubular rear base element 5. The ferrule holder 16 shown is arranged between the rear end 10 and the front end 11 of the tubular front base element 9. In the variant shown, the tubular front base element 9 comprises an annular groove configured to receive a seal 39. The annular groove and the seal 39 arranged therein can be arranged to surround the ferrule holder 16. The front end of the variant shown of the tubular rear base element 5 is designed as a cylindrical collar, which corresponds to the recess 12 and is press-fitted into the tubular front base element 9 to avoid the latter from popping out due to the load of the spring 15, which is generally in the range of 20N. In order to additionally increase the protection against an unwanted rotation of the tubular rear base element 5 relative to the tubular front base element 9 , an anti-twist element 34 is arranged at the front end of the tubular rear base element 5 .

[0050] The anti-twist element 34 shown engages with the recess of the tubular front base element 9 and prevents the tubular rear base element 5 from rotating relative to the tubular front base element 9. The shown variation of the optical fiber connector 1 includes an anti-kink boot in the form of a protective sleeve 21. The protective sleeve 21 shown is assembled by sliding it from the rear end of the tubular rear base element 5 onto the base element 2. The protective sleeve 21 is configured to seal the optical cable 7 and the base element 2 from environmental influences and additionally protect the base element 2 from collisions or protect the base element when it falls. The protective sleeve 21 shown is installed in a way that the tubular front base element 9 and the tubular rear base element 5 are partially surrounded by the protective sleeve 21. When the protective sleeve 21 is installed as shown in the figure so that it surrounds both the connecting element 25 and the tubular rear base element 5 and is attached to the tubular front base element 9 by a crimping ring, good results can be achieved. The protective sleeve 21 shown is made of a soft elastic material and is incorporated into a cable kink protector at its rear end. The protective sleeve 21 of the variant shown comprises a circumferential collar on the inside at its front end which engages with an annular recess arranged at the tubular front base element 9 in the mounted state.

[0051] Figure 4 Figure 4a The base element 2 of the optical fiber connector 1 is shown in Figure 4b , a cross-sectional view of the base element 2 is shown. The illustrated variant of the base element 2 is designed as a multi-part base element 2, which is configured to be interconnected to a plug element 36, which is used to interconnect the fiber optic connector 1 to, for example, a mating fiber optic connector. The illustrated base element 2 of the fiber optic connector 1 is assembled from a tubular rear base element 5 extending from a rear end to a front end in the longitudinal direction x and a tubular front base element 9 connected thereto. Figure 6b As can be best achieved, the shown tubular rear base element 5 forms the optical fiber deflection section 6. The shown variant of the tubular rear base element 5 comprises a first opening 43 at its rear end and a second opening 44 at its front end, which first opening 43 and second opening 44 are configured to allow at least one optical fiber 8 to extend through the tubular rear base element 5.

[0052] The tubular rear base element 5 forms a receiving space having a varying cross section between the first opening 43 and the second opening 44 in order to allow the deflection of at least one optical fiber 8. The diameter of the cross section of the receiving space is usually greater than the diameter of the first opening 43 and / or the second opening 44. When the diameter of the first opening 43 and / or the second opening 44 gradually widens to the diameter of the receiving space, a good result with respect to a smooth transition between the first opening 43 and / or the second opening 44 and the receiving space can be achieved. For a smooth transition, an introduction surface 45 can be arranged between the first opening 43 and the receiving space and / or between the second opening 44 and the receiving space. The variant shown comprises a deflection section having several zones: a first zone arranged adjacent to the front end of the tubular rear base element 5, and / or a second zone arranged adjacent to the rear end of the tubular rear base element 5, and a third zone arranged between the first zone and the second zone. The diameter of the third zone shown is greater than the diameter of the first zone and / or the second zone.

[0053] Figure 5 Figure 5a The optical fiber connector 1 is shown in Figure 5b , an enlarged detail view of a ferrule holder 16 of the optical fiber connector 1 is shown in FIG. The optical fiber connector comprises a ferrule 14, which is usually assembled with a tubular rear base element 5. The ferrule 14 can be arranged in a ferrule holder 16, which can be arranged inside a tubular front base element 9. The ferrule 14 is usually arranged to be deflectable against the force of a spring in the ferrule holder 16, which is arranged inside the tubular front base element 9, in front of the tubular rear base element 5. The ferrule 14 can be arranged inside the ferrule holder 16 together with a spring, which extends from a shoulder of the tubular rear base element 5 to the ferrule 14 in the longitudinal direction. When assembling the optical fiber connector, the ferrule holder 16 is usually inserted into the tubular front base element 9 from the rear end, and abuts against a shoulder of the tubular rear base element 5 in the installed state.

[0054] In order to prevent the ferrule holder 16 from rotating relative to the longitudinal direction, the ferrule holder 16 may include a protrusion that engages with a recess of the ferrule holder 16 in the installed state. The ferrule 14 is generally designed as a mechanical transfer (MT) ferrule 14. The MT ferrule 14 allows passive or active fiber optic connection packaging. At least one optical fiber is generally attached to the ferrule 14 with a fiber optic connector-grade heat-cured epoxy resin, and can be polished with various commercially available batches of connector polishers. The ferrule holder 16 may include a shoulder that can abut against a shoulder of the tubular rear base element 5 when inserted into the tubular front base element 9 from the rear end. In the installed state, the shoulder of the ferrule holder 16 can be fixed between the shoulder of the tubular rear base element 5 and the groove of the tubular front base element 9 attached thereto. In the installed state, the spring can be arranged adjacent to the front end of the tubular rear base element 5 and the ferrule 14. Depending on the design, the optical fiber connector can be configured to interconnect several optical fibers 8. Thus, the ferrule 14 may comprise several insertion locations arranged in a row and configured to receive several optical fibers 8. In a variant, the optical fiber connector is designed as a multi-fiber push-on connector (MPO connector).

[0055] Figure 6 Figure 6a The optical fiber connector 1 is shown in Figure 6b , an enlarged detail view of a connecting element 25 of a fiber optic connector 1 is shown. In order to be able to provide a preassembled base element 2, which consists of a tubular front base element 9, a tubular rear base element 5 and a ferrule holder 16 (with a ferrule 14 arranged therein, at least one optical fiber 8 with a predefined free length), it is necessary to attach the optical cable 7 to the base element 2. In the shown variant, the free fiber length of the at least one optical fiber 8 between the ferrule 14 and the end of the optical cable 7 (at which end the at least one optical fiber 8 leaves the optical cable 7) is adjusted by means of a connecting element 25, which is arranged to be adjustable in the longitudinal direction x.

[0056] The connecting element 25 shown is arranged at the rear end 10 of the tubular rear base element 5 and is configured to mechanically attach the optical cable 7 to the tubular rear base element 5. The connecting element 25 shown is designed as a cylindrical sleeve, which includes a collar for receiving the end section of the optical cable 7. The end section of the optical cable 7 can be attached to the collar by crimping and / or with an adhesive. The cylindrical sleeve (with the end section of the optical cable 7 attached thereto) can either be inserted into the rear end 10 of the tubular rear base element 5 or slid onto the rear end 10 of the tubular rear base element 5. If the connecting element 25 and the tubular rear base element 5 are arranged telescopically relative to each other during assembly and a recess 26 is formed between them, the free length of the optical fiber 8 can be adjusted, and the recess 26 is configured to receive adhesive in different longitudinal positions through the inlet 27. After the tubular rear base element 5 has been assembled to surround the prefabricated cable 7 assembly, a connecting element is arranged at the rear end of the tubular rear base element 5 and a ferrule holder 16 (with the ferrule 14 and spring 15 arranged therein) is arranged at the front end 11 of the tubular rear base element 5.

[0057] The tubular rear base element 5 is usually attached to the tubular front base element 3, thereby forming the base element 2. Thereby, the tubular rear base element 9 is inserted into the tubular front base element 9 together with the ferrule holder 16. After the insertion of the tubular rear base element 5 and the ferrule holder 16, the connecting element 25 is adjusted in the longitudinal direction x to adjust the free length of the at least one optical fiber 8 inside the tubular rear base element 5. In the variant shown, a crimping sleeve 30 is used as an attachment device, thereby fixing the connecting element 25 with respect to the longitudinal direction x. During the assembly of the optical fiber connector 1, the connecting element 25 is moved into the rear end of the tubular rear base element 5, and then after the ferrule holder 16 and the tubular front base element 9 are assembled, the connecting element is pulled back to define the desired free length of the at least one optical fiber 8 and fix it in the final position. With this, the free fiber length of the at least one optical fiber 7 can be easily controlled during the assembly process, which is essential for the function of the system. Typically, adhesive, such as epoxy, is injected through an inlet 27 in the form of a through hole arranged in the tubular rear base element 5. The hole may be arranged adjacent to the rear end of the tubular rear base element 5 and the recess 26 is filled with adhesive until excess adhesive leaves a vent hole typically arranged in the opposing half-shell of the tubular rear base element 5. Additionally, when an additional crimping sleeve 30 is mounted so as to surround the connecting element 25, additional stability and sealing of the crimped connection may be achieved.

[0058] The crimping sleeve 30 can be crimped onto the collar 46 of the connecting element 25 and thereby additionally fix the optical cable 7 to the connecting element 25 by the crimping force. In addition, the crimping sleeve 30 can be crimped onto the rear end of the tubular rear base element 5. Due to the crimping crimping sleeve 30, the assembly with the optionally applied uncured adhesive is instantly fixed, so that there is no need to pause during the assembly process until the adhesive for holding the connecting element 25 has solidified. This solution avoids squeezing at least one optical fiber 8, which can affect the optical performance. The connecting element 25 (with the crimping sleeve 30 mounted thereon) firmly attaches the optical cable 7 to the connecting element 25 by gluing. In this way, the optical cable 7 and thereby the at least one optical fiber 8 are prevented from being pushed into the base element 2. In order to achieve a mechanically stable attachment even under varying axial loads due to thermal expansion and / or creep, the recess 26 can be formed by corresponding grooves 28 in the tubular rear base element 5 and the connecting element 25. In a variant, the recess 26 is formed by an annular groove or a thread 28 arranged at the connection element 25 and / or a notch 29 arranged at the rear end of the tubular rear base element 5. A crimping sleeve 30 secures the position of the connection element 25 to the tubular rear base element 5. If an adhesive is used, the crimping sleeve 30 holds the connection element 25 in its position until the epoxy adhesive in the tubular rear base element 5 has solidified.

[0059] Figure 7 Figure 7a The optical fiber connector 1 is shown in Figure 7b , an enlarged detail view of the plug element 36 is shown in FIG. In order to connect the optical fiber connector 1 to, for example, a mating optical connector or a base station, the optical fiber connector 1 shown includes a plug element 36. The plug element 36 shown is arranged at the front end 11 of the tubular front base element 9 and includes a locking mechanism with a latch element 38, which automatically latches during connection. The latch element 38 shown is configured to interact and engage with a locking ring 40. The latch element 38 of the variant shown is designed as an elastically expandable locking ring 40, which is arranged concentrically with respect to the longitudinal direction x. In order to achieve a quick locking connection, the plug element 36 shown includes an actuating element 41, which includes a locking sleeve 42, which is arranged concentrically with respect to the longitudinal direction x and can be displaced along the longitudinal direction x to unlock the locking ring 40. In the variant shown, the tubular front base element 9 includes a circumferential recess arranged adjacent to the front end 11, which is configured to receive the latch element 38 for interconnecting the optical fiber connector 1 to the mating optical fiber connector. When pulled by the operator, the locking sleeve 42 interacts with the latching element 38 and retracts the latching element 38. In addition, in order to seal the connection from environmental influences in the installed state, a seal 39 can be arranged inside the tubular front base element 9 so as to surround the ferrule holder 16, which seal seals the connection from environmental influences in the installed state.

[0060] Figure 8 Figure 8a An alternative variant of the base element 2 of the optical fiber connector 1 is shown in Figure 8b 4 shows a cross-sectional view of the base element 2. The variant shown of the base element 2 is also designed as a multi-part base element 2 having a tubular rear base element 5 and a tubular front base element 9, which is configured to be interconnected to a plug element 36, which is used to interconnect the optical fiber connector 1 to, for example, a mating optical fiber connector. In the variant shown, the free fiber length of at least one optical fiber 8 between the ferrule 14 and the end of the optical cable 7 (at which end, at least one optical fiber 8 leaves the optical cable 7) is adjusted by a connecting element 25. The connecting element 25 shown is designed as a sleeve, which is arranged in the tubular rear base element 5. The connecting element 25 shown is arranged to be adjustable along the longitudinal direction x. Compared with the first variant of the base element 2 (as shown in FIG. 4), the connecting element 25 is arranged in the tubular base element 2 and is telescopically arranged relative to the longitudinal direction x during assembly. The connecting element 25 shown is arranged in a slidable manner in a hole in the tubular base element 2.

[0061] Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure.

[0062] List of reference numerals

[0063] 1Fiber Optic Connector

[0064] 2 Tubular base elements

[0065] 3 Rear end

[0066] 4 Front end

[0067] 5 Tubular posterior base element

[0068] 6 Fiber deflection section

[0069] 7. Optical Cable

[0070] 8 Fiber Optic

[0071] 9 Tubular front base element

[0072] 10 rear end portion (tubular front base element)

[0073] 11 front end portion (tubular front base element)

[0074] 12 recesses

[0075] 13 Anterior segment (tubular posterior base element)

[0076] 14 ferrule

[0077] 15 Spring

[0078] 16 Ferrule retainer

[0079] 17 Half Shell

[0080] 18 snap connection

[0081] 19 Shoulder

[0082] 20 Snap ring

[0083] 21 Protective sleeve

[0084] 22 crimping ring

[0085] 23 rear end (protective sleeve)

[0086] 24 Cable kink protector

[0087] 25 Connecting elements

[0088] 26 recesses

[0089] 27Entrance

[0090] 28 grooves / threads

[0091] 29 notches

[0092] 30 crimp sleeve

[0093] 31 shoulder (ferrule retainer)

[0094] 32 Shoulder (tubular rear base element)

[0095] 33 Insertion position (insert)

[0096] 34 Anti-twist element

[0097] 35 recess (anti-twist element)

[0098] 36 plug components

[0099] 37 Locking mechanism

[0100] 38 Latch element

[0101] 39 Seals

[0102] 40 Locking ring

[0103] 41 Actuating element

[0104] 42 locking sleeve

[0105] 43 First Opening

[0106] 44 Second opening

[0107] 45 Introduction Surface

[0108] 46 rings

Claims

1. An optical fiber connector (1), comprising: a. A tubular base element (2) extending in a longitudinal direction (x) from a rear end (3) to a front end (4) and comprising: i. a tubular rear base element (5) comprising on the inner side a fiber deflection section (6) configured to provide deflection space for at least one laterally deflected optical fiber (8) extending across the tubular rear base element (5) in the installed position of the fiber optic connector (1), and ii. a tubular front base element (9) comprising, at its rear end (10), a recess (12), in which the front section (13) of the tubular rear base element (5) is arranged in a form-fitting manner; b. An insert (14) arranged to be deflectable against the force of a spring (15) in an insert holder (16), said insert holder being arranged adjacent to the front end (4) of said tubular base element (2), inside said tubular front base element (9) and in front of said tubular rear base element (5).

2. The optical fiber connector (1) according to claim 1, wherein: The tubular rear base element (5) consists of two half-shells (17) interconnected to one another along a dividing plane extending along the longitudinal direction (x).

3. The optical fiber connector (1) according to any one of the preceding claims, wherein: The tubular front base element (9) and the tubular rear base element (5) are interconnected to each other by a press-fit connection.

4. The optical fiber connector (1) according to any one of the preceding claims, wherein: The tubular front base element (9) and the tubular rear base element (5) are interconnected to each other by a snap ring (20), which is arranged between opposite circumferential shoulders (19) of the tubular front base element (9) and the tubular rear base element (5), which form an undercut in the longitudinal direction (x).

5. The optical fiber connector (1) according to any one of the preceding claims, wherein: The ferrule holder (16) includes a shoulder (31) which abuts against a shoulder (32) of the tubular rear base element (5) when inserted into the tubular front base element (9) from the rear end (10).

6. The optical fiber connector (1) according to any one of the preceding claims, wherein: The spring (15) is arranged inside the ferrule holder (16), the spring extending in the longitudinal direction (x) from a shoulder (32) of the tubular rear base element (5) to the ferrule (14).

7. The optical fiber connector (1) according to any one of the preceding claims, wherein: At least one anti-twist element (34) is arranged at the front end (4) of the tubular rear base element (5), the at least one anti-twist element engaging with the recess (35) of the tubular front base element (9) and preventing the tubular rear base element (5) from rotating relative to the tubular front base element (9).

8. The optical fiber connector (1) according to any one of the preceding claims, wherein: The tubular front base element (9) and the tubular rear base element (5) are at least partially surrounded by a protective sleeve (21).

9. The optical fiber connector (1) according to claim 8, wherein: The protective sleeve (21) is attached to the tubular front base element (9) by means of a crimping ring (22) which is arranged outside the clamping ring (20).

10. An optical fiber connector (1), comprising: a. a tubular base element (2), the tubular base element extending in a longitudinal direction (x) from a rear end (3) to a front end (4) and comprising a fiber deflection section (6), the fiber deflection section being configured to provide deflection space for at least one laterally deflected optical fiber (8) extending at least partially across the tubular base element (2) in the installed position of the optical fiber connector (1); b. A connecting element (25), wherein: i. arranged at the rear end (3) of the tubular base element (2), the connecting element being configured to mechanically attach the optical cable (7) to the tubular base element (3), and ii. being arranged in an adjustable manner relative to the tubular base element (3) along the longitudinal direction (x) to adjust the free length of the optical fiber (8) extending between the connecting element (25) and the ferrule (14) at least during assembly before fixing; c. A ferrule (14) arranged to be deflectable against the force of a spring (15) in a ferrule holder (16) arranged adjacent the front end (4) of the tubular base element (2).

11. The optical fiber connector (1) according to claim 10, wherein: The connecting element (25) and the tubular base element (2) are arranged telescopically relative to each other during assembly and form a recess (26) therebetween, which is configured to receive adhesive in different longitudinal positions through an inlet (27).

12. The optical fiber connector (1) according to claim 11, wherein: The recess (26) is formed by an annular groove or a thread (28) arranged at the connecting element (25) and / or a notch (29) arranged at the rear end (3) of the tubular base element (2).

13. The optical fiber connector (1) according to claim 11, wherein: The connecting element (25) is slidably arranged in a hole in the tubular base element (2).

14. The optical fiber connector (1) according to any one of claims 10 to 13, wherein: A crimping sleeve (30) is attached to the rear end (3) of the tubular base element (2), the crimping sleeve (30) surrounding the connecting element (25) and being crimped to the rear end (3) of the tubular base element (3).

15. The optical fiber connector (1) according to any one of the preceding claims, wherein: A plug element (36) is arranged at the front end (4) of the tubular base element (2), the plug element (36) comprising a locking mechanism (37) with a latching element (38) which automatically latches during connection.

16. The optical fiber connector (1) according to any one of the preceding claims, wherein: A seal (39) is arranged inside the tubular base element (2) so as to surround the ferrule holder (16), which seal seals the connection from environmental influences in the mounted state.

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