Optical connection structure

Abstract

According to the present invention, it is possible to provide an optical connection structure in which optical fibers branched off from an optical cable are prevented from becoming bulky. An optical connection structure (1) comprises: an optical cable (2) that has a sheath (2a) and a plurality of optical fibers (2e1); a plurality of adapters (150) that are optically connected to the plurality of optical fibers (2e1); and an intermediate tube (3) that collectively covers the plurality of optical fibers (2e1) disposed between an end of the sheath (2a) and the adapters (150).

Description

Optical connection structure

[0001] The present invention relates to an optical connection structure. The present application claims priority based on Japanese Patent Application No. 2025-053316 filed in Japan on March 27, 2025, the content of which is incorporated herein by reference.

[0002] Patent Document 1 discloses a structure in which a plurality of branched optical cables extend from a branching portion of an optical cable.

[0003] Japanese Unexamined Patent Publication No. 2000-2811

[0004] In recent years, in facilities such as data centers, there has been a demand for arranging optical fibers and the like at higher density. In the structure disclosed in Patent Document 1, as the number of optical fibers increases, the number of branched optical cables increases, which causes a problem that the wiring volume of optical cords increases. Bulky cords make it difficult to install the optical connection structure in a rack or the like.

[0005] The present invention has been made in consideration of such circumstances, and an object of the present invention is to provide an optical connection structure that suppresses bulking of optical fibers branched from an optical cable.

[0006] In order to solve the above problem, the optical connection structure according to aspect 1 of the present invention includes: an optical cable having a sheath and a plurality of optical fibers; a plurality of adapters optically connected to the plurality of optical fibers; and an intermediate tube that collectively covers the plurality of optical fibers arranged between an end portion of the sheath and the adapters.

[0007] According to aspect 2 of the present invention, in the optical connection structure according to aspect 1, the intermediate tube may have higher flexibility than the optical cable.

[0008] Aspect 3 of the present invention is the optical connection structure according to aspect 1 or 2, including an optical module having a housing that accommodates the plurality of adapters, wherein a length of the intermediate tube between the end portion and the housing may be 10 cm or more.

[0009] Aspect 4 of the present invention is an optical connection structure according to any one of aspects 1 to 3, comprising an optical module having a housing for housing the plurality of adapters, wherein the intermediate tube extends from the end to the housing.

[0010] A fifth aspect of the present invention is an optical connection structure according to aspect 3 or 4, wherein a portion of the intermediate tube may be contained within the housing.

[0011] Aspect 6 of the present invention is an optical connection structure according to any one of aspects 3 to 5, which may include a fixing device for fixing the intermediate tube and the housing.

[0012] Aspect 7 of the present invention is an optical connection structure according to any one of aspects 1 to 6, which may include a plurality of optical modules arranged in series, a plurality of connecting fibers connecting the plurality of optical modules, and a connecting tube covering the plurality of connecting fibers.

[0013] Aspect 8 of the present invention is an optical connection structure according to any of aspects 1 to 6, which may include a plurality of optical modules arranged in parallel, a plurality of optical fibers connecting the optical cable and the plurality of optical modules, and a plurality of intermediate tubes covering each of the plurality of optical fibers.

[0014] According to the above embodiment of the present invention, it is possible to provide an optical connection structure that suppresses the bulkiness of optical fibers branched from an optical cable.

[0015] This is a schematic diagram showing the configuration of the optical connection structure of the first embodiment. This is an exploded view showing an example of the configuration of the optical cable in Figure 1A. This is a schematic diagram showing the configuration of the optical connection structure according to the first modified example. This is a perspective view of the optical module according to the first modified example. This is a schematic diagram showing the configuration of the optical connection structure according to the second modified example. This is a diagram showing a rack as the object to be installed. This is a diagram showing an example of the arrangement inside the rack in Figure 4A. This is a perspective view of the optical module of the first embodiment. This is a perspective view of the housing lid removed from Figure 5. This is a perspective view of the housing in Figure 6 further disassembled. This is a cross-sectional view of the optical module in Figure 5. This is a perspective view of the optical module of the second embodiment. This is a perspective view of the optical module, intermediate tube, etc., of the second embodiment. This is a perspective view showing the internal structure of the optical module of the second embodiment. This is a perspective view showing the adapter plate in Figure 11A rotated around the hinge and in the open state. This is a perspective view of the optical module in Figure 9 from a different angle.

[0016] (First Embodiment) The optical connection structure and optical module of the first embodiment will be described below with reference to the drawings. As shown in Figure 1A, the optical connection structure 1 comprises an optical cable 2 and an optical module 100. As shown in Figure 1B, the optical cable 2 has a sheath 2a, a retaining winding 2b, two pairs of tensile strength members 2c, a rip cord 2d, and a plurality of optical fiber units 2e. The retaining winding 2b surrounds the plurality of optical fiber units 2e. The retaining winding 2b and the optical fiber units 2e together are also called the "cable core". The sheath 2a houses the retaining winding 2b and the plurality of optical fiber units 2e. The tensile strength members 2c and the rip cord 2d are embedded in the sheath 2a. The tensile strength members 2c protect the optical fiber units 2e inside the sheath 2a from tension. The rip cord 2d is used to tear the sheath 2a during intermediate branching work, etc. Note that the structure of the optical cable 2 shown in Figure 1B is an example and can be changed.

[0017] Each of the multiple optical fiber units 2e has multiple optical fibers 2e1 and a bundle material 2e2. The bundle material 2e2 bundles the multiple optical fibers 2e1 together. The multiple optical fibers 2e1 may be, for example, intermittently fixed tape fibers. The intermittently fixed tape fibers have a structure in which adjacent optical fibers 2e1 are intermittently connected by multiple connecting parts. Alternatively, in the optical fiber unit 2e, the optical fibers 2e1 may not be tape-formed, but simply bundled by the bundle material 2e2.

[0018] Multiple optical connectors C can be inserted into the optical module 100. The optical connection structure 1 is a structure for optically connecting multiple optical fibers 2e1 contained in the optical cable 2 to multiple optical connectors C. A protective member 4 is provided at the end E of the sheath 2a in the optical cable 2. The protective member 4 covers and protects the end E of the sheath 2a. Optical fibers 2e1 extend from the end E. The optical connection structure 1 also includes an intermediate tube 3. Multiple optical fibers 2e1 extending between the end E of the sheath 2a and the optical module 100 are covered by the intermediate tube 3. The end of a tensile strength member 2c may be fixed to the protective member 4. In this case, the tensile strength member 2c can receive the tension acting on the optical cable 2 upstream of the protective member 4, and the optical fibers 2e1 can be effectively protected.

[0019] <First Modified Example of Optical Connection Structure> As shown in Figure 1A, only one optical module 100 may be connected to the optical cable 2. Alternatively, the first modified example shown in Figure 2A can also be adopted. In the first modified example, multiple optical modules 100 are connected in series to one optical cable 2. More specifically, multiple optical modules 100 are connected downstream of the optical module 100 connected by the intermediate tube 3. The optical modules 100 are connected to each other by connecting tubes 5. The connecting tubes 5 cover multiple connecting fibers F that connect the optical modules 100 to each other. The length, material, thickness, etc. of the connecting tubes 5 may be the same as those of the intermediate tube 3. The connecting fibers F may be the same as the optical fiber 2e1 of the optical cable 2, or they may be other optical fibers fusion-spliced ​​to the optical fiber 2e1.

[0020] Figure 2B is a perspective view showing the shape of the optical module 100 in the first modified example. As shown in Figure 2B, the optical module 100 may have a connection hole 115b for inserting the connecting tube 5. The connection hole 115b may be formed in the side wall 115 or in another location on the optical module 100.

[0021] <Second Modification of Optical Connection Structure> Alternatively, the second modification shown in Figure 3 can also be adopted. In the second modification, multiple optical modules 100 are connected in parallel to a single optical cable 2. More specifically, multiple intermediate tubes 3 are connected to the end E of the sheath 2a of the optical cable 2. Inside each of the multiple intermediate tubes 3 are multiple optical fibers 2e1 branched from the optical cable 2. Focusing on each intermediate tube 3, the upstream end is connected to the optical cable 2, and the downstream end is connected to the optical module 100.

[0022] <Installation Target> Figure 4A shows a rack 200 as an example of an installation target where the optical module 100 will be installed. In the example in Figure 4A, the rack 200 has an upper rack section 201 and a lower rack section 202. The upper rack section 201 is provided with a door section 203. The upper end of the upper rack section 201 is provided with a cable entry section 201a. The optical cable 2 is introduced into the inside of the rack 200 through the cable entry section 201a.

[0023] Figure 4B is a schematic diagram of the interior of the rack 200, which is exposed when the door 203 is opened. As shown in Figure 4B, multiple optical devices 204 are arranged inside the rack 200. The optical devices 204 include transceivers and the like that transmit and receive signals propagated by the optical cable 2. The optical devices 204 may also have control units such as a CPU and GPU. As shown in Figure 4B, an optical module 100 is arranged inside the rack 200. The optical module 100 is arranged, for example, in the ladder section located above the rack 200 on the outside of the rack 200, in the upper end section, the side section, near the optical devices 204, etc., on the inside of the rack 200. The multiple optical connectors C of the optical module 100 are connected to the optical devices 204. In this way, by applying the optical connection structure 1 to the rack 200, the bulkiness of cords inside the rack 200 can be reduced and the degree of freedom in the arrangement of optical connectors C can be increased.

[0024] The object on which the optical connection structure 1 is installed is not limited to the rack 200, and can be changed as appropriate. For example, the optical connection structure 1 may be placed on a so-called ladder or the like. Alternatively, the optical connection structure 1 may be placed on a rack or the like of optical communication equipment in a building such as a data center. The optical equipment 204 may be a so-called server device.

[0025] <Intermediate Tube> The intermediate tube 3 is flexible. The intermediate tube 3 is more flexible than the optical cable 2. For example, the thickness of the intermediate tube 3 is smaller than the thickness of the sheath 2a. For example, the thickness of the sheath 2a is 2 to 4 mm, and the thickness of the intermediate tube 3 is 0.5 to 2 mm. Also, the allowable bending radius of the intermediate tube 3 may be smaller than the allowable bending radius of the optical cable 2. For example, the allowable bending radius of the optical cable 2 is 125 mm, and the allowable bending radius of the intermediate tube 3 is 30 ± 5 mm.

[0026] Inside the intermediate tube 3, multiple optical fibers 2e1 are shuffled. Shuffled wiring is a wiring method in which multiple optical fibers 2e1 contained in one optical fiber unit 2e are branched and connected to multiple optical connectors C. In other words, shuffled wiring refers to grouping or changing the order of multiple optical fibers contained in an optical cable, etc., and connecting them to other cables or connectors, etc. To perform shuffled wiring, the length of the intermediate tube 3 is preferably 10 cm or more. Furthermore, the length of the intermediate tube 3 is more preferably 20 cm or more. The longer the intermediate tube 3, the easier it is to perform shuffled wiring, and the greater the flexibility of the intermediate tube 3. The greater the flexibility of the intermediate tube 3, the greater the freedom of arrangement when housing the intermediate tube 3 and optical module 100 in a rack, etc.

[0027] The intermediate tube 3 may house, for example, 48 or more optical fibers 2e1. As an example, the optical cable 2 houses a total of 864 optical fibers 2e1. In this case, in the structure of Figure 2A, 864 optical fibers 2e1 are housed in the intermediate tube 3. Alternatively, in the structure of Figure 3, 288 optical fibers 2e1 are housed in each of the three intermediate tubes 3. In these cases, one optical module 100 is equipped with a number of adapters 150 (described later) that can connect to 288 optical fibers 2e1.

[0028] Because the intermediate tube 3 is 10 cm or longer, even if 48 or more optical fibers 2e1 are housed inside the intermediate tube 3, shuffled wiring can be performed with ample space within the intermediate tube 3. In conventional technology, shuffled wiring is performed inside the so-called dam section. Since the dam section is generally made of rigid material with no flexibility, making the dam section longer presents the problem of difficulty in housing it inside racks 200, etc. For this reason, the length of the dam section must be shortened, and there is a problem of reduced manufacturing efficiency because shuffled wiring is performed within a short section.

[0029] To address the above issues, in this embodiment, shuffle wiring is performed inside the flexible intermediate tube 3. Specifically, shuffle wiring is performed in the section L shown in Figure 1A. Even if this section L is 10 cm or longer, because the intermediate tube 3 is flexible, the shuffle wiring section can be easily housed in the installation target object such as the rack 200, and further improvements in manufacturing efficiency can be obtained. The protective member 4 in this embodiment is a highly rigid member, similar to the conventional dam section. In this embodiment, the length of the protective member 4 is shorter than that of the intermediate tube 3.

[0030] Furthermore, in conventional configurations, numerous cords branch off from the end E of the sheath 2a of the optical cable 2, which can result in bulky cords. In this embodiment, the optical fibers 2e1 extending from the end E of the sheath 2a are covered collectively by the intermediate tube 3, thereby reducing bulk. Consequently, it becomes easier to place the optical module 100 on an installation target such as a rack 200.

[0031] Furthermore, shuffle wiring may be performed not only within the intermediate tube 3, but also within the housing 100a of the optical module 100. Alternatively, in the structure shown in Figure 2A, shuffle wiring may be performed within the connecting tube 5. The connecting tube 5 may have the same thickness and length as the intermediate tube 3.

[0032] <Optical Module 100> As shown in Figure 5, the optical module 100 includes a housing 100a. The housing 100a has a housing body 110 and a housing cover 120. In this embodiment, the housing 100a has two parts, but the housing 100a may be composed of one or three or more parts. The housing 100a as a whole is a rectangular parallelepiped. Figure 6 shows the state with the housing cover 120 removed. Note that in Figure 6, the optical fiber 2e1 wired inside the optical module 100 is not shown.

[0033] As shown in Figure 6, multiple adapters 150 are housed inside the housing 100a. Multiple optical connectors C can be inserted into each of the multiple adapters 150 from the outside of the housing 100a. Furthermore, the optical fibers 2e1 of the optical cable 2, which are inserted into the intermediate tube 3, are optically connected to each of the multiple adapters 150. In this way, the optical connection structure 1 can optically connect the optical cable 2 and the multiple optical connectors C. Note that the optical fibers 2e1 of the optical cable 2 may be connected directly to the adapter 150, or another optical fiber fusion-spliced ​​to the optical fiber 2e1 may be connected to the adapter 150.

[0034] As shown in Figure 6, the housing body 110 has a bottom wall 111, a front wall 112, an upstream side wall 113, a rear wall 114, and a downstream side wall 115. Figure 7 is a further exploded view of the housing 100a. As shown in Figure 7, an inlet 113a for introducing the intermediate tube 3 is formed in the upstream side wall 113. Multiple optical fibers 2e1 housed in the intermediate tube 3 are also introduced into the housing 100a through the inlet 113a.

[0035] In this specification, the positional relationships and shapes of each structure may be described using the directions represented by the X, Y, and Z axes shown in Figures 6 and 7. The X-axis is the axis along the direction in which the inlet 113a opens. The X-axis also coincides with the longitudinal direction of the intermediate tube 3 inserted through the inlet 113a. Hereinafter, the direction represented by the X-axis may be referred to as the longitudinal direction X. In the longitudinal direction X, the side (-X) toward the optical cable 2 from the inlet 113a may be referred to as the upstream side, and the opposite side (+X) may be referred to as the downstream side. The Y-axis represents one direction perpendicular to the X-axis. Hereinafter, the direction represented by the Y-axis may be referred to as the front-back direction Y. The Z-axis is perpendicular to both the X and Y axes. Hereinafter, the direction represented by the Z-axis may be referred to as the up-down direction Z. In the front-back direction Y, one side (+Y) may be referred to as the rear, and the opposite side (-Y) may be referred to as the front. In some cases, one side of the vertical Z direction (+Z) is referred to as "up," and the opposite side (-Z) is referred to as "down." However, the vertical Z direction does not necessarily coincide with the vertical direction.

[0036] As shown in Figure 6, the bottom wall 111 is plate-shaped and extends in the longitudinal direction X and the front-to-back direction Y. The front wall 112 is connected to the front end of the bottom wall 111. The front wall 112 extends upward from the bottom wall 111. The upstream side wall 113 is connected to the upstream end of the bottom wall 111. The upstream side wall 113 extends upward from the bottom wall 111. The rear wall 114 is connected to the rear end of the bottom wall 111. The rear wall 114 extends upward from the bottom wall 111. The downstream side wall 115 is connected to the downstream end of the bottom wall 111. The downstream side wall 115 extends upward from the bottom wall 111.

[0037] The upstream side wall 113 and the downstream side wall 115 face each other in the longitudinal direction X. The front wall 112 and the rear wall 114 face each other in the front-rear direction Y. The upstream side wall 113 and the downstream side wall 115 are plate-shaped and extend in the front-rear direction Y and the up-down direction Z. The front wall 112 and the rear wall 114 are plate-shaped and extend in the longitudinal direction X and the up-down direction Z.

[0038] As shown in Figure 5, the housing lid 120 has a top wall 121 and a lid-side front wall 122. The top wall 121 is plate-shaped and extends in the longitudinal direction X and the front-to-back direction Y. The top wall 121 faces the bottom wall 111 of the housing body 110 in the vertical direction Z. The lid-side front wall 122 extends downward from the front end of the top wall 121. The lid-side front wall 122 is plate-shaped and extends in the longitudinal direction X and the vertical direction Z. The lid-side front wall 122 is located on the same plane as the front wall 112 of the housing body 110.

[0039] Here, the housing lid 120 has a notch 123. Therefore, the dimension of the front wall 122 on the lid side in the longitudinal direction X is shorter than the dimension of the front wall 112 in the longitudinal direction X. The notch 123 forms an opening 100b in the housing 100a. Multiple adapters 150 inside the housing 100a are exposed through the opening 100b. Therefore, it is possible to connect multiple optical connectors C to multiple adapters 150 through the opening 100b.

[0040] As shown in Figures 6 and 7, an adapter plate 130 supporting multiple adapters 150 is arranged inside the housing 100a. The adapter plate 130 has a partition plate 131 and multiple support parts 132. The partition plate 131 is plate-shaped and extends in the longitudinal direction X and the front-to-back direction Y. The partition plate 131 faces the bottom wall 111 in the vertical direction Z. A gap is provided between the bottom wall 111 and the partition plate 131 in the vertical direction Z. This gap functions as a storage space S for storing the excess length portion of the optical fiber 2e1 (see Figure 8) inside the housing 100a. Note that the optical fiber 2e1 inside the housing 100a may be the optical fiber 2e1 of the optical cable 2 itself. Alternatively, the optical fiber 2e1 in the housing 100a may be another optical fiber fused to the optical fiber 2e1 of the optical cable 2.

[0041] As shown in Figure 7, the partition plate 131 has multiple through holes 131a. The number of through holes 131a may be one. Also, the bottom wall 111 has screw fastening portions 118. The adapter plate 130 is fixed to the housing body 110 by tightening screws (not shown) through the through holes 131a into the screw fastening portions 118. Note that the adapter plate 130 may be fixed to the housing body 110 by means other than screws. Multiple support portions 132 extend upward from the partition plate 131. Each support portion 132 has a first support side wall 132a and a second support side wall 132b. Multiple adapters 150 are supported between the first support side wall 132a and the second support side wall 132b in a vertical Z-direction (see Figure 6). The adapters 150 can be set into the support portions 132 from above.

[0042] <Adapter Angle> Figure 8 is a cross-sectional view of the optical module 100 along the longitudinal direction X and the front-to-back direction Y. In Figure 8, the straight line L1 is the normal to the wall surface 122a of the front wall 122 on the lid side. The straight line L2 is the straight line along the direction in which the optical connector C moves when the optical connector C is inserted into or removed from the adapter 150. Hereinafter, the direction along the straight line L1 may be referred to as the "normal direction L1," and the direction along the straight line L2 may be referred to as the "insertion / removal direction L2." In this embodiment, the normal direction L1 coincides with the front-to-back direction Y. Also, the angle θ between the normal direction L1 and the insertion / removal direction L2 is approximately 45°. That is, the insertion / removal direction L2 does not coincide with the normal direction L1 and is inclined with respect to the normal direction L1. The value of the angle θ is not limited to 45° and may be changed. In this embodiment, the insertion / removal direction L2 is inclined with respect to any outer surface of the housing 100a. However, the insertion / removal direction L2 may coincide with the normal direction L1. In other words, the adapter 150 may be positioned so that the optical connector C is inserted and removed perpendicular to the wall surface 122a.

[0043] <Connection Between Intermediate Tube and Housing> As shown in FIG. 8, an end portion of the intermediate tube 3 extends into the interior of the housing 100a. The end portion of the intermediate tube 3 is fixed to the housing 100a by a fixing member 140. The fixing member 140 includes a screw coupling member 141 and a fixing member 142. The fixing member 142 is fixed to an upstream side wall 113 of the housing 100a. The fixing member 142 has a cylindrical shape and is inserted through the inside of an introduction port 113a.

[0044] A male screw portion is formed on the outer circumferential surface of the fixing member 142. The screw coupling member 141 has a cylindrical shape and is inserted through the outside of the fixing member 142. A female screw portion is formed on the inner circumferential surface of the screw coupling member 141. When the screw coupling member 141 is rotated relative to the fixing member 142, the male screw portion and the female screw portion are screwed together, and the screw coupling member 141 moves in the longitudinal direction X relative to the fixing member 142. Along with this movement, the intermediate tube 3 is tightened by the fixing member 140, and the intermediate tube 3 is fixed to the housing 100a. With this structure, the optical fiber 2e1 inside the intermediate tube 3 is introduced into the housing 100a, and dropping of the intermediate tube 3 out of the housing 100a is suppressed.

[0045] Furthermore, an adhesive (not illustrated) may be filled into the inner side of the fixing member 142 and cured. In this case, the intermediate tube 3 can be more firmly fixed to the housing 100a by the adhesive.

[0046] <Wiring Path Inside Housing> As shown in FIG. 8, the optical fiber 2e1 in the intermediate tube 3 is introduced into the housing 100a through the introduction port 113a, and then wired in the storage space S below the partition plate 131. In FIG. 8, for ease of viewing the wiring path of the optical fibers 2e1, instead of displaying the optical fibers 2e1 one by one, the plurality of optical fibers 2e1 following the same wiring path are displayed as a single bundle. As shown in FIG. 7, a first guide portion 116 and a second guide portion 117 are arranged in the storage space S. The guide portions 116 and 117 are substantially columnar and extend upward from the bottom wall 111. The first guide portion 116 is located more upstream than the second guide portion 117. An arc-shaped groove 117a is formed in the second guide portion 117.

[0047] The outer circumferential surface 116a of the first guide portion 116, the outer circumferential surface 117b of the second guide portion 117, and the inner surface of the groove 117a function as guide surfaces that guide the wiring path of the optical fiber 2e1. For this reason, the outer circumferential surface 116a, the outer circumferential surface 117b, and the inner surface of the groove 117a have a radius of curvature larger than the allowable bending radius of the optical fiber 2e1. By wiring the optical fiber 2e1 along the outer circumferential surface 116a, the outer circumferential surface 117b, and the groove 117a, it is possible to suppress the bending of the optical fiber 2e1 at a radius smaller than the allowable bending radius. As a result, an increase in connection loss is suppressed.

[0048] Furthermore, within the storage space S, the optical fiber 2e1 initially heads downstream (+X side), then folds back and heads upstream (-X side). Near the upstream end of the partition plate 131, the optical fiber 2e1 exits the storage space S, heads upwards towards the partition plate 131, and connects to the adapter 150. As such wiring paths within the housing 100a, it is possible to select a first path that folds back along the outer surface 116a of the first guide portion 116, a second path that folds back inside the groove 117a, and a third path that folds back along the outer surface 117b of the second guide portion 117. There is variation in the excess length of the multiple optical fibers 2e1 from the inlet 113a to the multiple adapters 150. Therefore, by selecting the first path, second path, or third path within the housing 100a, it is possible to create a wiring path that matches the length of the excess length.

[0049] <Optical fiber accommodation density within the housing> For example, 288 optical fibers 2e1 are introduced into the housing 100a. In other words, a total of 288 optical fibers 2e1 are optically connected to the adapter 150 inside the housing 100a. As an example, the occupied volume of the housing 100a is 250 cm³. ３ ~660cm ３ In this example, the density of optical fibers 2e1 relative to the volume occupied by the housing 100a is 0.44 to 1.15 fibers / cm². ３This is how it works. According to this embodiment, it is possible to realize such a high-density optical module 100 by devising the arrangement of the storage space S and wiring paths for the optical fiber 2e1 within the housing 100a, and by tilting the orientation of the adapter 150 (i.e., the insertion / removal direction L2 of the optical connector C) with respect to the wall surface 122a. The "occupied volume" is the total volume occupied by the housing 100a when it is assumed that all openings of the housing 100a are closed.

[0050] As described above, the optical connection structure 1 of this embodiment comprises an optical cable 2 having a sheath 2a and a plurality of optical fibers 2e1, a plurality of adapters 150 optically connected to the plurality of optical fibers 2e1, and an intermediate tube 3 that covers the plurality of optical fibers 2e1 collectively, positioned between the end E of the sheath 2a and the adapters 150. With this optical connection structure 1, the intermediate tube 3 covers the optical fibers 2e1 collectively, which reduces bulk compared to the conventional case where a large number of cords with optical connectors branch off from the end of the optical cable.

[0051] Furthermore, the intermediate tube 3 is more flexible than the optical cable 2. For example, the thickness of the intermediate tube 3 is less than the thickness of the sheath 2a. This ensures the flexibility of the intermediate tube 3, making it possible to easily house the intermediate tube 3 inside an installation target such as a rack 200.

[0052] Furthermore, the optical connection structure 1 includes an optical module 100 having a housing 100a that accommodates a plurality of adapters 150. Preferably, the length of the intermediate tube 3 between the end E of the sheath 2a and the housing 100a is 10 cm or more. In this case, the flexibility of the intermediate tube 3 is increased, and it becomes possible to shuffle the optical fibers 2e1 inside the intermediate tube 3.

[0053] Furthermore, it is preferable that the intermediate tube 3 extends from the end E of the sheath 2a to the housing 100a. This allows for effective protection of the optical fiber 2e1 between the end E and the housing 100a.

[0054] Furthermore, it is preferable that a portion of the intermediate tube 3 is inserted into the housing 100a. This prevents the optical fiber 2e1 from being exposed at the connection point between the intermediate tube 3 and the housing 100a.

[0055] Furthermore, the optical module 100 is equipped with a fixing device 140 that secures the intermediate tube 3 to the housing 100a. This prevents the intermediate tube 3 from coming loose from the housing 100a.

[0056] Furthermore, as shown in Figure 2A, the optical connection structure 1 may include a plurality of optical modules 100 arranged in series, a plurality of connecting fibers F connecting the plurality of optical modules 100, and a connecting tube 5 covering the plurality of connecting fibers F. Alternatively, as shown in Figure 3, the optical connection structure 1 may include a plurality of optical modules 100 arranged in parallel, a plurality of optical fibers 2e1 connecting the optical cable 2 and the plurality of optical modules 100, and a plurality of intermediate tubes 3 covering each of the plurality of optical fibers 2e1. With these configurations, a large number of optical connectors C can be branched from a single optical cable 2, and the overall bulkiness can be reduced.

[0057] (Second Embodiment) Next, a second embodiment of the present invention will be described, which has the same basic configuration as the first embodiment. For this reason, the same reference numerals are used for similar components, and their descriptions are omitted. Only the differences will be described.

[0058] As shown in Figure 9, the optical module 100' of this embodiment has a different shape from the optical module 100 of the first embodiment. In addition, an attachment 300 for mounting to an object such as a rack 200 can be attached to the optical module 100' of this embodiment. Since the optical module 100' has a structure similar to the optical module 100 of the first embodiment, corresponding parts will be described by adding an apostrophe ('') to their reference numerals. For example, the housing 100a, housing body 110, and housing lid 120 in the first embodiment correspond to the housing 100a', housing body 110', and housing lid 120' in the second embodiment, respectively.

[0059] As shown in Figures 9 and 10, the intermediate tube 3 of this embodiment has irregularities on its surface. However, the surface of the intermediate tube 3 does not need to be irregular. Also, the intermediate tube 3 of this embodiment may be the same as the intermediate tube 3 described in the first embodiment.

[0060] Figure 11A is a perspective view showing the internal structure of the optical module 100'. In this embodiment as well, the optical fiber 2e1 (not shown) inserted through the fixing device 140' is introduced into the housing 100a' through the inlet 113a'. As shown in Figure 11B, in this embodiment, the adapter plate 130' and the housing body 110' are rotatably connected by a hinge H. By rotating the adapter plate 130' around the hinge H, the storage space S between the partition plate 131' and the bottom wall 111' can be greatly opened. This makes it easier to wire the optical fiber 2e1 into the storage space S.

[0061] Figure 12 is a view of the optical module 100' of Figure 9 from a different angle. As shown in Figure 12, the attachment 300 has a connecting portion 301, a mounting portion 302, and an attachment body portion 303. The connecting portion 301 is plate-shaped and is the part that connects to the housing 100a'. The connecting portion 301 has a hole (not shown) for inserting a screw 304. The screw 304 is screwed into the housing 100a'. This connects the attachment 300 to the housing 100a'. The mounting portion 302 is plate-shaped and extends in a plane substantially perpendicular to the connecting portion 301. The mounting portion 302 has two mounting holes 302a. The mounting holes 302a are used, for example, to screw the attachment 300 to an object to be installed, such as a rack 200.

[0062] The attachment body 303 connects the connecting part 301 and the mounting part 302. A screw 305 is also attached to the attachment body 303. The screw 305 can be used when attaching the attachment 300 to an object to be installed, such as a rack 200. As shown in Figure 9, a hook part 306 (fixing part) is formed on the attachment body 303. The hook part 306 can be used to hook the attachment 300 onto an object to be installed, such as a rack 200.

[0063] Thus, the attachment 300 is equipped with multiple means for attaching it to the object to be installed. This increases the degree of freedom in positioning the attachment 300 when attaching it to the object to be installed. Note that the attachment 300 may not be equipped with some of these attachment means, or it may be equipped with other attachment means.

[0064] As described above, the optical connection structure 1 of this embodiment comprises an optical cable 2 having a sheath 2a and a plurality of optical fibers 2e1, an optical module 100' having a plurality of adapters 150 optically connected to the plurality of optical fibers 2e1 and a housing 100a' housing the plurality of adapters 150, an intermediate tube 3 that covers the plurality of optical fibers 2e1 arranged between the end E of the sheath 2a and the housing 100a', and an attachment 300 for attaching the optical module 100' to the object to be installed. With this configuration, the optical module 100 can be easily attached to the object to be installed using the attachment 300. In addition, since the optical fibers 2e1 between the optical cable 2 and the optical module 100 are covered collectively by the intermediate tube 3, bulkiness can be reduced compared to the case where a large number of cords are arranged.

[0065] Furthermore, the attachment 300 may have a fixing portion (hook portion 306) for securing the housing 100a' to the object to be installed. In this case, the housing 100a' can be suspended from the object to be installed using the hook portion 306. Therefore, the housing 100a' can be attached to the object to be installed more easily.

[0066] Furthermore, the attachment 300 may have mounting holes 302a for fixing the housing 100a' to the object to be installed. In this case, the housing 100a' can be screwed to the object to be installed using the mounting holes 302a. Therefore, the housing 100a' can be attached to the object to be installed more easily.

[0067] Furthermore, the object to be installed may be a rack 200. In this case, the optical module 100' can be easily attached to the rack 200 using the attachment 300. In addition, since the optical fiber 2e1 is covered collectively by the intermediate tube 3, the bulkiness can be reduced compared to when many cables are arranged inside the rack 200.

[0068] The technical scope of the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the invention.

[0069] For example, the optical connection structure 1 of the above embodiment includes an optical cable 2, an intermediate tube 3, and an optical module 100, but some of these components may be omitted.

[0070] Furthermore, without departing from the spirit of the present invention, the components in the above-described embodiments may be replaced with well-known components as appropriate, and the above-described embodiments and modifications may be combined as appropriate. For example, by combining the first embodiment and the second embodiment, multiple optical modules 100' equipped with attachments 300 as shown in Figure 9 may be connected to a single optical cable 2 as shown in Figure 2A or Figure 3.

[0071] Furthermore, the features of the optical cable 2, intermediate tube 3, optical module 100, etc., described in the first embodiment may be appropriately combined with the optical connection structure of the second embodiment. Examples of such features include the angle of the adapter 150, the connection between the intermediate tube 3 and the housing 100a, the wiring path within the housing 100a, the density of optical fibers within the housing 100a, and shuffled wiring.

[0072] Furthermore, in the embodiments described above, the optical cable 2 includes a plurality of optical fiber units 2e having a plurality of optical fibers 2e1, and the plurality of adapters 150 or optical connectors C include a plurality of optical fibers. In the plurality of optical fiber wiring between the plurality of optical fiber units 2e and the plurality of adapters 150 or optical connectors C, shuffle wiring may be used to optically couple each optical fiber 2e1 constituting at least one optical fiber unit 2e with optical fibers constituting at least two plurality of adapters 150 or optical connectors C. In this case, shuffle wiring means that each optical fiber 2e1 constituting at least one optical fiber unit 2e is optically coupled with optical fibers constituting at least two plurality of adapters 150 or optical connectors C. The optical fibers 2e1 constituting the optical fiber unit 2e may also be inserted into the adapters 150 or optical connectors C and optically connected. In this case, a portion of the optical fibers 2e1 inserted into the adapters 150 or optical connectors C corresponds to "optical fibers included in the adapters 150 or optical connectors C". Alternatively, the adapter 150 or optical connector C may include an optical fiber other than the optical fiber 2e1 that constitutes the optical fiber unit 2e, and the optical fiber 2e1 and the optical fiber included in the adapter 150 or optical connector C may be optically coupled. These two configurations are included in the statement that "each optical fiber constituting at least one optical fiber unit is optically coupled with optical fibers constituting at least two or more adapters or optical connectors."

[0073] According to the above embodiments of the present invention (including modifications), it is possible to provide an optical connection structure that suppresses the bulkiness of optical fibers branched from an optical cable.

[0074] 1…Optical connection structure 2…Optical cable 2a…Sheath 2e1…Optical fiber 3…Intermediate tube 5…Connecting tube 100, 100'…Optical module 100a, 100a'…Housing 140, 140'…Fixing device 150…Adapter F…Connecting fiber

Claims

1. An optical connection structure comprising: an optical cable having a sheath and multiple optical fibers; multiple adapters optically connected to the multiple optical fibers; and an intermediate tube that covers the multiple optical fibers collectively, positioned between the end of the sheath and the adapters.

2. The optical connection structure according to claim 1, wherein the intermediate tube is more flexible than the optical cable.

3. The optical connection structure according to claim 1 or claim 2, comprising an optical module having a housing for housing the plurality of adapters, wherein the length of the intermediate tube between the end and the housing is 10 cm or more.

4. The optical connection structure according to any one of claims 1 to 3, comprising an optical module having a housing for housing the plurality of adapters, wherein the intermediate tube extends from the end to the housing.

5. The optical connection structure according to claim 3 or claim 4, wherein a portion of the intermediate tube is contained within the housing.

6. The optical connection structure according to any one of claims 3 to 5, further comprising a fixing device for fixing the intermediate tube and the housing.

7. An optical connection structure according to any one of claims 1 to 6, comprising: a plurality of optical modules arranged in series; a plurality of connecting fibers connecting the plurality of optical modules; and a connecting tube covering the plurality of connecting fibers.

8. An optical connection structure according to any one of claims 1 to 6, comprising: a plurality of optical modules arranged in parallel; a plurality of optical fibers connecting the optical cable and the plurality of optical modules; and a plurality of intermediate tubes covering each of the plurality of optical fibers.

Images