Fusion splicer and pitch conversion member

Abstract

To provide a fusion splicer and the like capable of collectively fusion-splicing a plurality of optical fibers that require rotational alignment.SOLUTION: A pitch conversion member 1 includes: a main body part 3 having a plurality of grooves 7 formed in an upper surface; and a lid part 5 for closing upper portions of the grooves 7. The pitch conversion member 1 is used in a fusion splicer to regulate pitches of a plurality of optical fibers accommodated in the grooves 7 by gradually changing the pitches of the plurality of grooves 7 so as to become narrower from a rear side toward a front side. Each of the grooves 7 is formed in a gently curved shape from the rear side toward the front side.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a fusion splicer and the like that is excellent in alignment workability. [Background technology]

[0002] A fusion splicer is used to connect optical fibers together. The fusion splicer places optical fibers held in a pair of holders, butts them together, between electrodes, and fuses the tips of the optical fibers together using an arc, thereby connecting the optical fibers together.

[0003] When fusing optical fibers together, alignment work is required to align the tip positions of the optical fibers. For this reason, conventionally, alignment was performed by placing the optical fibers opposite each other and capturing an image of the tip positions of the optical fibers from the side (perpendicular to the axial direction of the optical fibers) using an imaging unit.

[0004] On the other hand, when an optical fiber is not a typical single-core optical fiber but has a circumferential direction relative to its cross-sectional shape, such as a polarization-maintaining fiber or a multi-core fiber, alignment is required not only in the tip position but also in the rotational direction. In other words, not only alignment in the so-called XY directions at the tip position of the optical fiber but also rotational alignment in the circumferential direction around the axial direction of the optical fiber is required.

[0005] In order to perform such rotational alignment of an optical fiber, for example, an optical fiber rotation device has been proposed that has a shaft portion in which a fiber groove for arranging the optical fiber is formed, and a mounting portion on which the tip of the optical fiber is placed facing the end portion opposite the shaft portion, and that supports the shaft portion on a support portion so that the rotating member can be rotated around the axis of the optical fiber (Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] Japanese Patent Application Laid-Open No. 2005-164985 Summary of the Invention [Problem to be solved by the invention]

[0007] In conventional single-core fibers, ribbon fibers are used, which have a structure in which multiple optical fibers are connected in a ribbon shape in order to shorten the time required for cable installation work. In this case, it is desirable to be able to fusion-splice multiple optical fibers together.

[0008] 8(a) is a partial schematic diagram of fusion splicing two conventional optical fibers 100. The optical fibers 101 constituting the optical fiber ribbon 100 are held at a predetermined interval by a V-groove member 103, and arc discharge between electrodes 105 melts the tips of the optical fibers 101 to perform fusion splicing.

[0009] On the other hand, as mentioned above, as multi-core fibers become more widespread, ribbon core wires made up of a plurality of multi-core fibers have been proposed. In this case, too, it is desirable to splice a plurality of multi-core fibers together.

[0010] 8(b) is a partial schematic diagram of fusion splicing ribbon fibers 100a each consisting of a plurality of optical fibers 101a having circumferential directionality, such as multi-core fibers. As described above, in order to splice multi-core fibers together, rotational alignment is required around the optical fiber axis so that the positions of the plurality of cores and markers match those of the optical fibers to be spliced.

[0011] However, the optical fiber rotating unit 107 for rotating the optical fiber 101a is much larger than the diameter of the optical fiber 101a, and in order to rotationally align each optical fiber 101a of the ribbon fiber 100a, it is necessary to first separate the optical fibers 101a constituting the ribbon fiber 100a at a predetermined interval and then perform rotational alignment using each optical fiber rotating unit 107. For this reason, the optical fibers 101a are arranged at intervals corresponding to at least the width dimension of the optical fiber rotating unit 107.

[0012] On the other hand, when multiple optical fibers 101a are fusion-spliced ​​together using commonly used arc discharge, it is necessary to narrow the spacing between the optical fibers 101a and realign them using the V-groove member 103 so that the spacing between the electrode rods falls within the interval (several millimeters) required to generate a stable arc discharge. For this reason, the optical fibers 101a are arranged between the optical fiber rotating part 107 and the V-groove member 103 so that they are curved such that the spacing between them gradually narrows.

[0013] Here, typically, when fusing the optical fibers 101a together after starting discharge by the electrode 105, the optical fibers 101a may be moved in the axial direction to butt the tips of the optical fibers 101a together. For example, the optical fiber rotator 107 holding the optical fibers 101a may be moved toward the V-groove member 103 to move the optical fibers 101a toward the opposing optical fibers 101a.

[0014] However, as described above, the optical fiber 101a is curved between the optical fiber rotating unit 107 and the V-groove member 103, and therefore even if the optical fiber 101a is pushed forward in the optical fiber rotating unit 107, the optical fiber 101a may not move axially in the V-groove member 103, and the movement of the optical fiber rotating unit 107 may be absorbed by a change in the curvature of the optical fiber 101a (for example, buckling). If the movement of the optical fiber 101a varies in this way, there is a risk of a deterioration in the fusion quality.

[0015] Similarly, when the optical fiber 101a is rotated in the optical fiber rotation unit 107, the rotation of the optical fiber 101a in the optical fiber rotation unit 107 may be relaxed in the curved portion between the optical fiber rotation unit 107 and the V-groove member 103. In this case, the rotation angle of the optical fiber 101a in the optical fiber rotation unit 107 may not match the rotation angle at the tip of the optical fiber 101a, which may reduce the accuracy of rotational alignment.

[0016] The present invention has been made in view of the above problems, and has as its object to provide a fusion splicer or the like that is capable of collectively fusing a plurality of optical fibers that require rotational alignment. [Means for solving the problem]

[0017] In order to achieve the above-mentioned object, the first invention is a fusion splicer having multiple optical fiber rotating units, comprising: a holder mounting unit on which holders that hold optical fibers are placed; multiple optical fiber rotating units arranged in tandem in front of the holder mounting unit; a V-groove member in front of the optical fiber rotating unit that holds each optical fiber to be spliced ​​at a predetermined pitch; and a pitch conversion member between the optical fiber rotating unit and the V-groove member, having a groove that converts the tandem pitch of the optical fiber rotating units to the pitch of the V-groove member, wherein the depth and width of the groove are larger than the diameter of the optical fiber that can be held by the V-groove member.

[0018] For a pair of opposing optical fibers to be fused, the optical fiber rotating unit may not be positioned on the side holding one of the optical fibers, the V-groove member may be positioned in front of the holder mounting unit, and the optical fiber rotating unit and the pitch conversion member may be positioned only on the side where the other optical fiber is positioned.

[0019] The pitch conversion member may have a main body portion in which the groove is formed, and a lid portion that closes an upper portion of the groove.

[0020] A pin may be disposed inside the bent portion of the groove, and the pin may function as a guide when inserting the optical fiber into the groove.

[0021] A recess having approximately the same depth as the groove may be formed in a predetermined area including a part of the groove.

[0022] The pitch conversion member may be configured such that each divided body separated by the groove is a separate body, at least some of the divided bodies are movable from a reference position, an optical fiber can be placed between each divided body while the divided body is moved from the reference position, and the groove can be formed between the divided bodies by returning the divided body to the reference position.

[0023] The pitch change members may be arranged respectively in front of and behind the optical fiber rotation unit, and for each pitch change member, the total length of the groove in which any one optical fiber is arranged may be approximately the same as the total length of the groove in which any other optical fiber is arranged.

[0024] An alignment groove capable of accommodating multiple optical fibers may be formed in front of the pitch conversion member, and the multiple grooves may be concentrated in the alignment groove, making it possible to align the multiple optical fibers inside the alignment groove.

[0025] According to a first aspect of the present invention, in a fusion splicer having multiple optical fiber rotators, a pitch conversion member having a groove for converting the parallel pitch of the optical fiber rotators to the pitch of the V-groove member is provided between the multiple optical fiber rotators and a V-groove member that holds the optical fibers at a predetermined pitch. This makes it possible to regulate the path of the optical fiber from the optical fiber rotator to the V-groove member, and to prevent the optical fiber from freely deforming between the optical fiber rotator and the V-groove member. As a result, for example, the optical fiber can be reliably moved in the axial direction, and deterioration of fusion quality can be prevented.

[0026] Furthermore, by arranging the optical fiber rotator and pitch changer only on the side holding one of the pair of opposing optical fibers to be fused, there is no need to arrange an optical fiber rotator or pitch changer on the side of the other optical fiber, which allows the fusion splicer to be made more compact.

[0027] Furthermore, by providing a lid that covers the upper part of the pitch conversion member, the optical fiber in the groove is prevented from jumping out of the groove, and the optical fiber can be more reliably accommodated in the groove.

[0028] Furthermore, by placing a pin inside the curved part of the groove, it can function as a guide when inserting the optical fiber into the groove, making it easy to insert the optical fiber into a curved groove.

[0029] Furthermore, by forming a recess having substantially the same depth as the groove in a predetermined range including a part of the groove, the operation of pushing the optical fiber into the groove becomes easier.

[0030] Furthermore, by configuring the pitch conversion member with multiple segments separated by grooves and making at least some of the segments movable from a reference position, it is possible to form grooves between the segments by moving the segments from the reference position, placing optical fibers between each segment, and then returning the segments to the reference position, which makes it easier to insert the optical fibers into the grooves.

[0031] Furthermore, by disposing the pitch conversion members in front of and behind the optical fiber rotating unit, the total length of the groove in which any one optical fiber is disposed can be made substantially the same as the total length of the groove in which any other optical fiber is disposed for each pitch conversion member, thereby making it possible to make the lengths of the individual optical fibers separated from the ribbon fiber to the splice unit substantially uniform.

[0032] Furthermore, by forming an alignment groove capable of accommodating a plurality of optical fibers in front of the pitch changer, the plurality of optical fibers can be aligned inside the alignment groove, allowing the optical fibers to be arranged close to each other in front of the pitch changer.

[0033] The second invention is an optical fiber pitch changer used in a fusion splicer, which changes the pitch of a groove that accommodates multiple optical fibers, and is characterized in that it has a main body portion in which grooves are formed, and a pin is arranged inside the bent portion of the groove, and the pin functions as a guide when inserting the optical fiber into the groove.

[0034] A recess having approximately the same depth as the groove may be formed in a predetermined area including a part of the groove.

[0035] According to the second invention, in a fusion splicer having multiple optical fiber rotators, the path of the optical fiber from the optical fiber rotator to the V-groove member can be regulated, and free deformation of the optical fiber between the optical fiber rotator and the V-groove member can be suppressed. In particular, by arranging a pin inside the curved portion of the groove, it can function as a guide when inserting the optical fiber into the groove. Therefore, the optical fiber can be easily inserted into a curved groove.

[0036] Furthermore, by forming a recess having substantially the same depth as the groove in a predetermined range including a part of the groove, the operation of pushing the optical fiber into the groove becomes easier.

[0037] The third invention is a pitch change member for optical fibers used in a fusion splicer, in which the pitch of grooves in which multiple optical fibers are accommodated is changed, characterized in that the main body in which the grooves are formed is composed of separate divided bodies partitioned by the grooves, at least some of the divided bodies are movable from a reference position, optical fibers can be placed between each of the divided bodies when the divided bodies are moved from the reference position, and the grooves can be formed between the divided bodies by returning the divided bodies to the reference position.

[0038] According to the third aspect of the present invention, in a fusion splicer having multiple optical fiber rotators, the path of the optical fiber from the optical fiber rotator to the V-groove member can be regulated, and free deformation of the optical fiber between the optical fiber rotator and the V-groove member can be suppressed. In particular, by configuring the pitch conversion member with multiple divided bodies separated by grooves and making at least some of the divided bodies movable from a reference position, it is possible to form grooves between the divided bodies by moving the divided bodies from the reference position, placing the optical fiber between each divided body, and then returning the divided body to the reference position. This makes it easy to insert the optical fiber into the groove.

[0039] In the second and third aspects of the present invention, the material of the portion that comes into contact with the optical fiber may be made of a fluorine-based resin. By doing so, the optical fiber can be smoothly moved. [Effects of the Invention]

[0040] According to the present invention, it is possible to provide a fusion splicer or the like that is capable of collectively fusing a plurality of optical fibers that require rotational alignment. [Brief explanation of the drawings]

[0041] [Figure 1] 2A is a plan view of the pitch conversion member 1 (main body 3), FIG. 2B is a cross-sectional view taken along line AA in FIG. 2A, and FIG. 2C is a cross-sectional view taken along line BB in FIG. [Figure 2] 1(a) and 1(b) are diagrams showing a method for inserting an optical fiber 15 into a groove 7 of a pitch changer 1, and FIG. 1(c) is a diagram showing the optical fiber 15 housed in the groove 7. FIG. [Figure 3] FIG. 2 is a schematic diagram showing the internal configuration of the fusion splicer 10 when the pitch conversion member 1 is in use. [Figure 4] (a) is a plan view of the pitch conversion member 1a (main body 3a) in the standard state, (b) is a diagram showing the state in which the divided body 23a has been moved, and (c) is a diagram showing the state in which the divided body 23b has been further moved. [Figure 5]4(c) shows the state in which the optical fiber 15 is arranged, and FIG. 4(b) shows the state in which the divided bodies 23a and 23b have been returned to their original state. [Figure 6] 1A is a plan view of the pitch conversion member 1b (main body portion 3b), FIG. 1B is a cross-sectional view taken along line CC in FIG. 1A, and FIG. 1C is a cross-sectional view taken along line DD in FIG. [Figure 7] FIG. 1A is a schematic diagram of the inside of a fusion splicer 10a in which a pitch conversion member 1d is arranged, and FIG. 1B is a cross-sectional view taken along line EE in FIG. [Figure 8] 1(a) is a schematic diagram showing a method for bulk-fusion splicing a plurality of optical fibers 101 of a conventional ribbon fiber 100, and FIG. 1(b) is a schematic diagram showing a method for bulk-fusion splicing a plurality of optical fibers 101a of a conventional ribbon fiber 100a. DETAILED DESCRIPTION OF THE INVENTION

[0042] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1(a) is a plan view of the main body 3 of the pitch change member 1 (a perspective view of the lid 5 of the pitch change member 1), Fig. 1(b) is a cross-sectional view taken along line AA in Fig. 1(a), and Fig. 1(c) is a cross-sectional view taken along line BB in Fig. 1(a).

[0043] The pitch changer 1 has a main body 3 with multiple grooves 7 formed on the upper surface, and a lid 5 that closes the upper part of the main body 3 (grooves 7). The pitch changer 1 is used in a fusion splicer and is a member for regulating the pitch of multiple optical fibers accommodated in the grooves 7 by gradually narrowing the pitch of the multiple grooves 7 from the rear to the front (hereinafter, the wide-pitch side on the left side of FIG. 1(a) is referred to as the rear of the pitch changer 1, and the narrow-pitch side on the right side of FIG. 1(a) is referred to as the front of the pitch changer 1).

[0044] In the illustrated example, four grooves 7 are formed, but there is no particular limitation on the number of grooves 7. Furthermore, the cross-sectional shape of the grooves 7 is substantially rectangular, but there is no particular limitation on the cross-sectional shape of the grooves 7.

[0045] Each groove 7 is formed in a gentle curve from the rear to the front. The grooves 7 are arranged substantially parallel to each other on the front side. Pins 9 are arranged on the inner periphery of the curved portion of the groove 7 in at least some of the grooves 7. As will be described in detail later, the pins 9 function as guides when inserting the optical fiber into the groove 7. For this reason, it is desirable to arrange the pins 9 in a portion where the radius of curvature of the curved shape of the groove 7 is equal to or less than a predetermined value. In the illustrated example, the pins 9 are arranged inside the curved portions of the grooves 7 only in the two grooves 7 located on both outer sides in the parallel direction (width direction), but pins 9 may also be arranged in the two grooves 7 in the center of the parallel direction.

[0046] Furthermore, in at least some of the grooves 7, recesses 11 having approximately the same depth as the depth of the grooves 7 are formed in a predetermined range including a portion of the grooves 7. In other words, the recesses 11 are portions where the grooves 7 are widened. In the illustrated example, in the region sandwiched between the pins 9, recesses 11 are formed for two grooves 7 located on both outer sides in the parallel direction (width direction). Note that the recesses 11 may be formed to include all of the grooves 7.

[0047] 2(a) is a diagram showing the process of inserting an optical fiber 15 into a groove 7 of the pitch changer 1 (main body 3). Normally, the optical fiber 15 has a certain degree of rigidity and is stable in a straight shape. Therefore, in order to insert the optical fiber 15 into a groove 7 with a predetermined radius of curvature or less, the optical fiber 15 needs to be bent to match the shape of the groove 7.

[0048] In the pitch change member 1, a pin 9 is formed on the inner circumferential side of the bend in the portion of the groove 7 where the curvature is large. Therefore, as shown in FIG. 2(a), by arranging the optical fiber 15 so that it is hooked on the pin 9, the optical fiber 15 can be easily bent into a roughly S-shape similar to the shape of the groove 7. In addition, a recess 11 is formed in part of the groove 7. Therefore, as shown in FIG. 2(b), by pressing the optical fiber 15 with a finger near the recess 11 (part F in the figure), the optical fiber 15 can be easily inserted into the groove 7.

[0049] 2(c) is a cross-sectional view showing the optical fiber 15 housed in the groove 7. As mentioned above, the cross-sectional shape of the groove 7 does not need to be rectangular, but since the groove 7 does not accurately position the optical fiber 15, it is desirable to have a certain degree of clearance around (width and height) the optical fiber 15 housed in the groove 7. In this way, the curved shape of the optical fiber 15 can be restricted to some extent, and the optical fiber 15 can be moved axially or rotated in a rotational direction with little resistance while maintaining the curved shape of the groove 7.

[0050] In order to make it easier for the optical fiber 15 to move in the axial direction, for example, the inner surface of the groove 7 (the portion that comes into contact with the optical fiber 115) may be made of a material with a small coefficient of friction (such as a fluororesin). Furthermore, if the bottom surface of the groove 7 is made into a curved surface that matches the cross-sectional shape of the optical fiber 15, the contact area between the optical fiber 15 and the inner surface of the groove 7 increases, resulting in high frictional resistance. Therefore, it is desirable that the inner surface of the groove 7 be shaped so as to come into point contact with the optical fiber 15 in cross section. Furthermore, the smoothness may be further improved by optimizing the roughness of the inner surface of the groove 7 or by applying wax or lubricant to the inner surface of the groove 7.

[0051] Next, a fusion splicer having a plurality of optical fiber rotating units and using a pitch conversion member 1 will be described. FIG. 3 is a schematic diagram showing the structure of the fusion splicer 10. The fusion splicer 10 is provided with a pair of holder mounting units 16. Each of the holder mounting units 16 has a holder (not shown) disposed thereon for holding an optical fiber 15. In this embodiment, the holder holds a ribbon fiber 13 made up of a plurality of optical fibers 15.

[0052] A plurality of optical fibers 15 are separated from one of the ribbon fibers 13 (on the left side in the figure) and introduced into a plurality of optical fiber rotation units 17 that are arranged in front of the holder placement unit 16. Each of the optical fiber rotation units 17 can rotate the optical fiber 15 around the axis of the optical fiber 15 as the rotation axis. In other words, the plurality of optical fibers 15 can be rotationally aligned separately.

[0053] Furthermore, a pitch change member 1 is disposed in front of the optical fiber rotating unit 17 (the direction toward the optical connection unit where the electrode 21 is disposed is defined as the front), and further in front of that is disposed a V-groove member 19 that holds the optical fibers 15 to be connected at a predetermined pitch. In other words, the pitch change member 1 is disposed between the optical fiber rotating unit 17 and the V-groove member 19. As described above, the pitch change member 1 has grooves 7 that convert the juxtaposition pitch of the optical fiber rotating unit 17 to the pitch of the V-groove member 19.

[0054] The optical fibers 15 taken out in front of the optical fiber rotating unit 17 are aligned to the pitch of the V-groove member 19 by the grooves 7 of the pitch conversion member 1, and are held by clamps (not shown) in the V-groove member 19. The optical fibers 15 aligned to a predetermined pitch by the V-groove member 19 are placed between a pair of electrodes 21 opposite the optical fibers 15 to be connected.

[0055] 3, the fusion splicer may have a symmetrical structure with respect to the opposing ribbon fiber 13, but instead of arranging the optical fiber rotating unit 17 on the side (right side in the drawing) that holds one of the pair of opposing ribbon fiber 13 to be fusion spliced, a V-groove member 19 may be arranged directly in front of the holder placement unit 16. In other words, the optical fiber rotating unit 17 and the pitch conversion member 1 may be arranged only on the side (left side in the drawing) where the other ribbon fiber 13 is arranged.

[0056] When performing rotational alignment, first, an image of the end faces of a pair of opposing optical fibers 15 is captured by a reflecting member or the like (not shown). Next, at least one of the pair of opposing optical fibers 15 is held by the optical fiber rotating unit 17 and rotated around the axial direction of the optical fiber 15 as the rotation axis, thereby aligning the circumferential positions of the end faces of the opposing optical fibers 15.

[0057] Conventional alignment work in the X and Y directions can be performed in the same manner as conventional methods. After alignment, the reflecting member is retracted, the pair of optical fibers 15 is brought close to each other, arc discharge is generated between the electrodes 21, and the pair of optical fibers 15 is further moved toward the tip end to butt the tip ends together, thereby performing rotational alignment and fusion splicing of the optical fibers 15. At this time, as described above, the depth and width of the groove 7 are large compared to the diameter of the optical fiber 15 that can be held by the V-groove member 19, so the optical fiber 15 can move freely within the groove 7.

[0058] As described above, according to the present embodiment, in a fusion splicer 10 having a plurality of optical fiber rotators 17, by disposing the pitch conversion member 1 between the plurality of optical fiber rotators 17 and the V-groove member 19, it is possible to regulate the path of the optical fiber 15 between the optical fiber rotator 17 and the V-groove member 19. This prevents the optical fiber 15 from freely deforming between the optical fiber rotator 17 and the V-groove member 19, and prevents the optical fiber 15 from bending or buckling when moving in the axial direction, thereby ensuring that the optical fiber 15 is moved in the axial direction. This prevents a decrease in fusion quality.

[0059] Furthermore, by arranging the optical fiber rotation unit 17 and the pitch conversion member 1 only on the side holding one of a pair of opposing ribbon fiber 13 to be fusion spliced, there is no need to arrange the optical fiber rotation unit 17 or the pitch conversion member 1 on the side of the other ribbon fiber 13. This allows the fusion splicer 10 to be made smaller.

[0060] Furthermore, by providing a lid that covers the upper part of the pitch conversion member 1, the optical fibers 15 in the grooves 7 are prevented from jumping out of the grooves 7, and the optical fibers 15 can be accommodated in the grooves 7 more reliably.

[0061] Furthermore, by arranging the pin 9 inside the curved portion of the groove 7, it can function as a guide when inserting the optical fiber 15 into the groove 7. Therefore, the optical fiber 15 can be easily inserted into the groove 7 having a curved shape.

[0062] Furthermore, by forming recesses 11 having substantially the same depth as the depth of grooves 7 in a predetermined range including a part of grooves 7, the task of pushing optical fibers 15 into grooves 7 becomes easier.

[0063] Next, a second embodiment will be described. Fig. 4(a) is a schematic diagram showing a pitch conversion member 1a according to the second embodiment. In the following description, the same components as those in the above-described embodiment will be given the same reference numerals, and redundant description will be omitted. In the following description, illustrations of the lid portion 5, pin 9, recess 11, etc. will be omitted.

[0064] The second embodiment has a configuration substantially similar to that of the first embodiment, but differs in that the main body 3a of the pitch change member 1a is made up of separate segments 23a, 23b, and 23c separated by grooves 7. The main body 3a has a two-layer structure, with the segments 23a, 23b, and 23c disposed on the lower base member 25.

[0065] In the state shown in Figure 4(a), segment 23c is placed approximately in the center on base member 25, segment 23b is placed on both sides of segment 23c with a predetermined gap between them, and segment 23a is placed on both sides of segment 23b with a predetermined gap between them. The spaces between segments 23a, 23b, and 23c form grooves 7. That is, grooves 7 are formed by base member 25 and the side surfaces of each adjacent segment. The state shown in Figure 4(a) (i.e., the state where all grooves 7 have the width to accommodate the optical fiber) is taken as the reference state.

[0066] 4(b) is a diagram showing a state in which divided body 23a has been moved from the reference state. Divided body 23a can slide outward in both width directions (left and right directions in the figure) relative to base member 25. That is, divided body 23a can be moved in a direction away from divided body 23b. Note that a stopper (not shown) is provided on base member 25, which prevents divided body 23a from completely separating from base member 25 and restricts movement beyond a predetermined limit.

[0067] Figure 4(c) is a diagram showing a state in which divided body 23b has been further moved from the state shown in Figure 4(b). Divided body 23b is rotatably attached to base member 25 near its rear end (lower side in the figure) on the inner side in the width direction, and its front end (upper side in the figure) can be rotated toward both outer sides. In other words, divided body 23b can be moved in a direction away from divided body 23c. Note that a stopper (not shown) is provided on base member 25, which restricts divided body 23b from moving beyond a predetermined angle.

[0068] 5(a) is a diagram showing a state in which the optical fibers 15 are arranged between the segments 23a, 23b, and 23c, in contrast to the state shown in FIG. 4(c). In the main body 3a of the pitch change member 1a, the segments 23a and 23b are moved from their reference positions to widen the gaps between the segments, allowing the optical fibers 15 to be arranged in a substantially straight line. This eliminates the need to insert the optical fibers 15 into the grooves 7 while bending them into a predetermined shape.

[0069] Figure 5(b) is a diagram showing the state in which the divided bodies 23a and 23b have been returned to their reference positions from the state in Figure 5(a). As described above, when the divided bodies 23a and 23b are returned to their reference positions, curved grooves 7 are formed between the divided bodies 23a, 23b, and 23c. That is, the optical fiber 15 that was disposed between the divided bodies 23a, 23b, and 23c is curved into the predetermined shape of the groove 7 and accommodated within the groove 7 as the divided bodies 23a and 23b move.

[0070] At the front end of the main body 3a, the four optical fibers 15 are sandwiched from both sides by the segments 23a. That is, at the front end of the main body 3a, no segments are disposed between the four optical fibers 15, and the grooves 7 form a single wide groove. More specifically, at the reference position, at the front end of the pitch change member 1a, the spacing between the segments 23a is approximately equal to the number times the diameter of the optical fibers 15, and the optical fibers 15 are held in close contact with each other in the width direction. Therefore, in the pitch change member 1b, the multiple optical fibers 15 can be arranged in parallel at a pitch approximately equal to the outer diameter of the optical fibers 15.

[0071] The main body 3a has a stopper (not shown) for holding the divided bodies 23a and 23b in the reference position, and the divided bodies 23a and 23b will not open due to the restoring force of the curved shape caused by the rigidity of the optical fiber 15. Also, the lid may be fixed before returning to the reference position (the state of FIG. 5(a)).

[0072] According to the second embodiment, the same effects as those of the first embodiment can be obtained. Furthermore, the main body 3a of the pitch changer 1a has multiple segments 23a, 23b, and 23c, and at least some of the segments 23a and 23b are movable from their reference positions. Therefore, the optical fibers 15 can be arranged between the segments 23a, 23b, and 23c while the segments 23a and 23b are moved from their reference positions. By returning the segments 23a and 23b to their reference positions, grooves 7 can be formed between the segments 23a, 23b, and 23c. That is, when arranging the optical fibers 15, the intervals between the segments can be increased, and the optical fibers 15 can be arranged in a substantially linear manner. Therefore, the optical fibers 15 can be easily arranged in the main body 3a. Furthermore, by returning the segments 23a and 23b to their reference positions, the optical fibers 15 can be easily accommodated in the curved grooves 7.

[0073] The shape and arrangement of the segments 23a, 23b, and 23c are not limited to the illustrated example. For example, as described above, the number of grooves 7 is not limited to four, and the number of segments may be increased depending on the number of grooves 7 (the number of optical fibers), and in that case, the shape, arrangement, movement direction, etc. of each segment can be changed as appropriate.

[0074] Next, a third embodiment will be described. Fig. 6(a) is a plan view of a main body 3b of a pitch changer 1b, Fig. 6(b) is a cross-sectional view taken along line CC in Fig. 6(a), and Fig. 6(c) is a cross-sectional view taken along line DD in Fig. 6(a). Pitch changer 1b is substantially the same as pitch changer 1, but an alignment groove 27 capable of accommodating multiple optical fibers is formed in the front of pitch changer 1b (upper part in Fig. 6(a)), and multiple grooves 7 are aggregated in alignment groove 27 in plan view.

[0075] The alignment grooves 27 have approximately the same width as the grooves 7 in a plan view, but are formed deeper than the grooves 7 from the upper surface of the main body 3b. As described above, each groove 7 has a depth that allows some clearance to be formed when the optical fibers 15 are accommodated therein. On the other hand, the alignment grooves 27 are formed to a depth (i.e., approximately the number times the depth of the grooves 7) that allows multiple optical fibers 15 to be accommodated in parallel in the vertical direction (thickness direction of the main body 3b).

[0076] According to the third embodiment, it is possible to obtain the same effects as in the first embodiment. Furthermore, by forming the alignment groove 27 on the front end side of the main body 3b, the plurality of optical fibers 15 can be aligned in the alignment groove 27. In this case, each part is arranged so that the alignment direction in the alignment groove 27 and the alignment direction in the V-groove member 19 coincide with each other.

[0077] Next, a fourth embodiment will be described. Fig. 7(a) is a plan view showing the arrangement of each part in a fusion splicer 10a using pitch changers 1c and 1d. In this embodiment, pitch changers 1c and 1d are arranged in front of and behind an optical fiber rotating unit 17, respectively. That is, of a pair of ribbon optical fibers 13 (see Fig. 3) to be spliced, a pair of pitch changers 1c and 1d is used for one ribbon optical fiber 13.

[0078] Both pitch change member 1c and pitch change member 1d are formed so that the path lengths of grooves 7 increase at approximately constant intervals from one end to the other in the width direction. For example, in pitch change member 1c, groove 7a at one end side in the width direction (left side in the figure) has the shortest path length, and grooves 7b, 7c, and 7d have longer path lengths at approximately constant intervals in that order. Similarly, in pitch change member 1d, groove 7d at one end side in the width direction (right side in the figure) has the shortest path length, and grooves 7c, 7b, and 7a have longer path lengths at approximately constant intervals in that order.

[0079] The grooves of the pitch change member 1c and the pitch change member 1d are formed to be substantially rotationally symmetrical. That is, the grooves 7a of the pitch change member 1c and the grooves 7d of the pitch change member 1d have substantially the same shape, the grooves 7b of the pitch change member 1c and the grooves 7c of the pitch change member 1d have substantially the same shape, the grooves 7c of the pitch change member 1c and the grooves 7b of the pitch change member 1d have substantially the same shape, and the grooves 7d of the pitch change member 1c and the grooves 7a of the pitch change member 1d have substantially the same shape.

[0080] Therefore, by arranging the grooves 7a, 7b, 7c, and 7d of the pitch change members 1c and 1d so that they face each other across the optical fiber rotation portion 17, the total length of the grooves in which any one optical fiber 15 is arranged in each of the pitch change members 1c and 1d (for example, the total length of the grooves 7a) can be made approximately the same as the total length of the grooves in which any other optical fiber 15 is arranged (for example, the total length of the grooves 7b).

[0081] Also, alignment grooves 27a are formed on the front end side (upper side in the figure) of the pitch changer 1d. Fig. 7(b) is a cross-sectional view taken along the line E-E in Fig. 7(a). In this embodiment, alignment grooves 27a are formed on the front end side of the pitch changer 1d, with a depth sufficient to accommodate multiple optical fibers 15 in a parallel arrangement. In this embodiment, the depth direction of the alignment grooves 27a corresponds to the width direction of the pitch changer 1d. That is, the alignment grooves 27a are formed to a predetermined depth (downward in the figure) in an area that opens upward (an area that communicates with grooves 7a, etc.), and are formed so that they extend to a predetermined depth (rightward in the figure) from that area in the width direction.

[0082] In this embodiment, the depth direction of the alignment groove 27a (to the right in FIG. 7(b)) is opposite to the side on which the groove 7a is arranged. As described above, in the pitch change member 1d, the groove 7a has the longest path length and is curved more greatly. For example, the groove 7a of the pitch change member 1d is formed so as to curve more greatly from the rear end side (lower side in the figure) to the front end side (upper side in the figure), and from one end side (left side in the figure) to the other end side (right side in the figure).

[0083] When the optical fibers 15 are accommodated in the grooves 7a having such a configuration, a force acts on the front end side of the pitch changer 1d to straighten the optical fibers 15 toward the other end side (the right side in the figure) due to the rigidity of the optical fibers 15. Therefore, by forming the depth direction of the alignment grooves 27a to coincide with the direction in which the curvature of the optical fibers 15 tends to return, the optical fibers 15 can be aligned in the alignment grooves 27a so as to be in close contact with each other in the depth direction.

[0084] According to the fourth embodiment, it is possible to obtain the same effects as those of the first embodiment. In addition, by using a pair of pitch change members 1c and 1d sandwiching the optical fiber rotating unit 17 and making the path lengths of the optical fibers in the pitch change members 1c and 1d approximately constant, it is possible to make the lengths of the optical fibers 15 separated from the ribbon fiber 13 to the splice portions constant.

[0085] Furthermore, by forming the alignment grooves 27a, the optical fibers 15 can be aligned in close contact with each other.

[0086] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical scope of the present invention is not limited to the above-described embodiments. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the technical ideas described in the claims, and it is understood that these modifications and alterations also fall within the technical scope of the present invention. [Explanation of symbols]

[0087] 1, 1a, 1b, 1c, 1d....Pitch conversion members 3, 3a, 3b……Main body 5……Lid part 7, 7a, 7b, 7c, 7d……Groove 9...pin 10, 10a...Fusion splicer 11....Recess 13....Core ribbon 15...Optical fiber 16...Holder placement section 17...Optical fiber rotating part 19……V groove member 21... Electrode 23a, 23b, 23c……divided body 25...Base member 27, 27a... Alignment groove 100, 100a.... Ribbon fiber 101, 101a...optical fiber 103……V groove member 105……Electrode 107...Optical fiber rotating part

Claims

1. A fusion splicer having a plurality of optical fiber rotating units, a holder placement section on which a holder for holding an optical fiber is placed; a plurality of optical fiber rotating units arranged in front of the holder placement unit; a V-groove member in front of the optical fiber rotating unit, which holds the optical fibers to be spliced ​​at a predetermined pitch; a pitch conversion member having a groove between the optical fiber rotating portion and the V-groove member for converting the pitch of the optical fiber rotating portion to the pitch of the V-groove member; Equipped with A fusion splicer characterized in that the depth and width of the groove are greater than the diameter of the optical fiber that can be held by the V-groove member.

2. the optical fiber rotating unit is not disposed on the side holding one of a pair of opposing optical fibers to be fused, and the V-groove member is disposed in front of the holder mounting unit; 2. The fusion splicer according to claim 1, wherein the optical fiber rotating section and the pitch changing member are disposed only on the side where the other optical fiber is disposed.

3. 2. The fusion splicer according to claim 1, wherein the pitch conversion member has a main body portion in which the groove is formed, and a lid portion that closes an upper portion of the groove.

4. 2. The fusion splicer according to claim 1, wherein a pin is disposed inside the bent portion of the groove, and the pin functions as a guide when inserting the optical fiber into the groove.

5. 2. The fusion splicer according to claim 1, wherein a recess having a depth substantially equal to that of the groove is formed in a predetermined range including a part of the groove.

6. 2. The fusion splicer according to claim 1, characterized in that the pitch conversion member is configured such that the divided bodies partitioned by the grooves are each composed of separate bodies, at least some of the divided bodies are movable from a reference position, and an optical fiber can be placed between each of the divided bodies while the divided bodies are moved from the reference position, and the grooves can be formed between the divided bodies by returning the divided bodies to the reference position.

7. the pitch conversion members are disposed in front of and behind the optical fiber rotating unit, 2. The fusion splicer according to claim 1, wherein, for each of the pitch change members, the total length of the groove in which any one optical fiber is placed is approximately the same as the total length of the groove in which any other optical fiber is placed.

8. an alignment groove capable of accommodating a plurality of optical fibers is formed in front of the pitch conversion member, and the plurality of grooves are gathered together in the alignment groove; 2. The fusion splicer according to claim 1, wherein a plurality of optical fibers can be aligned inside said alignment groove.

9. An optical fiber pitch changing member used in a fusion splicer, in which the pitch of a groove in which a plurality of optical fibers are accommodated changes, a body portion having a groove formed therein; A pitch conversion member characterized in that a pin is disposed inside the bent portion of the groove, and the pin functions as a guide when inserting the optical fiber into the groove.

10. 10. The pitch change member according to claim 9, wherein a recess having substantially the same depth as the depth of the groove is formed in a predetermined range including a part of the groove.

11. An optical fiber pitch changing member used in a fusion splicer, in which the pitch of a groove in which a plurality of optical fibers are accommodated changes, A pitch conversion member characterized in that the main body portion in which the grooves are formed is composed of separate divided bodies partitioned by the grooves, at least some of the divided bodies are movable from a reference position, an optical fiber can be placed between each of the divided bodies when the divided bodies are moved from the reference position, and the grooves can be formed between the divided bodies by returning the divided bodies to the reference position.

12. 12. The pitch change member according to claim 9, wherein the portion that comes into contact with the optical fiber is made of a fluorine-based resin.

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