Fusion machine

Abstract

To provide a fusion machine enabling accurate alignment.SOLUTION: A pair of electrodes are arranged oppositely in a direction substantially perpendicular to an opposite direction of a pair of optical fibers. When a pair of optical fibers 21 is arranged oppositely, a reflection member 23 can be moved between the optical fibers 21 by a reflection member elevation drive unit. An end surface imaging unit 19a can capture an image reflected by the reflection member 23. The reflection member 23 is covered with a shielding member 25 when the reflection member 23 is retracted. That is, the shielding member 25 is arranged between the reflection member 23 and the optical fiber 21 (fusion part) side when the reflection member 23 is in the retracted state. The shielding member 25 can be opened and closed with the vertical operation of the reflection member 23, and the shielding member 25 is closed in conjunction with the movement of the reflection member 23 when the reflection member 23 is retracted from the opposite position of the optical fibers 21.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a fusion splicer having excellent alignment workability. [Background technology]

[0002] A fusion splicer is used to connect optical fibers together. The fusion splicer butts optical fibers held in a pair of holders together, places them 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, it is necessary to perform an alignment process to align the tip positions of the optical fibers. Conventionally, therefore, alignment was performed by placing the optical fibers opposite each other and capturing an image of the tip position of the optical fiber from the side (perpendicular to the axial direction of the optical fiber) using an imaging unit.

[0004] On the other hand, in the case of a so-called polarization-maintaining fiber or multi-core fiber that has a circumferential direction relative to the cross-sectional shape, rather than a typical single-core optical fiber, alignment is required not only in the tip position but also in the rotation direction. In other words, not only alignment in the so-called XY directions of the optical fiber, but also rotation 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, a reflective member is placed between the opposing parts of the optical fibers, the end face of the optical fiber is reflected by an imaging section to be imaged, and rotational alignment is performed by observing the end face (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2004-53625 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, in the conventional method, the reflecting surface of the reflecting member may become dirty due to discharge or debris from the optical fiber, which may degrade the image quality of the optical fiber end face observation. This may make it difficult to achieve accurate alignment.

[0008] The present invention has been made in consideration of the above problems, and has an object to provide a fusion splicer capable of highly accurate alignment. [Means for solving the problem]

[0009] In order to achieve the above-mentioned object, the present invention provides a fusion splicer for connecting optical fibers, the fusion splicer comprising: an optical fiber holding section for holding a pair of optical fibers facing each other; a pair of electrodes arranged facing each other in a direction approximately perpendicular to the facing direction of the pair of optical fibers; a reflecting member movable between the optical fibers when the pair of optical fibers is arranged facing each other; an imaging section for capturing an image reflected by the reflecting member; and an alignment drive section capable of aligning the pair of optical fibers by rotating at least one of the pair of optical fibers about an axis along the facing direction of the pair of optical fibers, the reflecting member having a reflecting surface that reflects an image of an end face of each of the optical fibers toward the imaging section, the reflecting member being arranged between the reflecting member and the optical fibers when the reflecting member is retracted from a position where the optical fibers face each other, and configured to close in conjunction with the movement of the reflecting member when the reflecting member is retracted from the position where the optical fibers face each other. A pair The fusion machine is characterized by having a shielding member.

[0010] It is desirable to have a protection mechanism that has a sensor capable of detecting the state of the reflective member or the shielding member, and that enables discharge between the electrodes when the sensor detects that the reflective member has been retracted from the position facing the optical fiber or that the shielding member has been closed.

[0011] Opening the shielding member Ku No wall is formed on the side surface in the direction of the opening of the shielding member. KuThe wall may be formed on a side surface different from the direction.

[0012] When the shielding member is in a closed state, When the tip ends of the pair of shielding members are butted against each other, The shielding member A pair tip By A convex shape facing the opposing position of the optical fiber is formed It is desirable to do so.

[0013] A pair of side imaging units are arranged in a direction different from that of the imaging unit, The opening and closing direction of the shielding member is used to image the alignment position of the optical fiber. The above It is desirable that the direction be different from the direction in which the lateral imaging unit is disposed.

[0014] The shielding member has a shielding portion at its tip, and a pair of the shielding members When it is closed, The shielding portions at the tip portions of the shielding members are butted against each other, and the butted portions of the shielding portions are formed obliquely with respect to a direction perpendicular to the opening / closing direction, In a plan view, tip portions of the pair of shielding members may partially overlap each other.

[0015] The shielding member is desirably made of austenitic stainless steel.

[0016] When the shielding member is closed, it is desirable that the shortest distance between the electrode and the shielding member is longer than the inter-electrode distance, and it is further desirable that the shortest distance between the electrode and the shielding member is at least twice the inter-electrode distance.

[0017] According to the present invention, when a reflective member capable of reflecting the end face of an optical fiber is retracted from between opposing optical fibers, the shielding member closes in conjunction with the movement of the reflective member, so that the reflective member can be reliably protected from contamination by the shielding member during discharge.

[0018] In particular, by using a sensor that can detect when the reflective member is retracted from the position facing the optical fiber or when the shielding member is closed, it is possible to prevent discharge from occurring in a state where the reflective member is not retracted or the shielding member is not closed due to a malfunction or other reason.

[0019] Furthermore, by not forming a wall portion on the side surface of the shielding member in the opening / closing direction, it is possible to prevent interference with the optical fiber holding portion, etc., that is arranged in the opening / closing direction of the shielding member when the shielding member is opened.

[0020] Similarly, by making the tip of the shielding member convex toward the opposing position of the optical fiber and narrowing the upper end of the shielding member when the shielding member is closed, it is possible to prevent interference with the optical fiber holding part, etc., that is arranged in the opening and closing direction of the shielding member when the shielding member is opened.

[0021] Furthermore, by setting the opening and closing direction of the shielding member to a direction different from the arrangement direction of the lateral imaging unit that images the alignment position of the optical fiber, it is possible to prevent foreign objects, etc. from falling onto the lateral imaging unit when the shielding member is opened or closed.

[0022] Furthermore, by making the tips of the pair of shielding members overlap in a planar view when the shielding members are closed, it is possible to more reliably prevent foreign matter from entering the interior compared to when the shielding members are simply butted together.

[0023] Furthermore, by making the shielding member from austenitic stainless steel, it is possible to ensure high mechanical strength even at high temperatures, and also to ensure high corrosion resistance against ozone generated by discharge.

[0024] Furthermore, when the shielding member is closed, the shortest distance between the electrode and the shielding member is set to at least twice the distance between the electrodes, thereby making it possible to suppress leakage discharge to the shielding member. Effect of the Invention

[0025] According to the present invention, a fusion splicer capable of highly accurate alignment can be provided. [Brief description of the drawings]

[0026] [Figure 1] FIG. [Diagram 2] FIG. [Diagram 3] 1A is a view seen from the axial direction of the optical fiber 21, and FIG. 1B is a view seen from the axial direction of the electrode 7. FIG. [Figure 4] FIG. 2 is an enlarged perspective view of a reflecting member 23 and a shielding member 25. [Diagram 5] 1A is a side view showing a state in which the shielding member 25 is closed, and FIG. 1B is a side view showing a state in which the reflecting member 23 is raised and the shielding member 25 is open. [Figure 6] 5(a) is a diagram showing the state of the shielding portions 29a and 29b in FIG. 5(a), and FIG. 5(b) is a diagram showing the state of the shielding portions 29a and 29b in FIG. 4(b). [Figure 7] 5(a) is a diagram showing another state of the shielding portions 29a and 29b of FIG. 5(a), and FIG. 5(b) is a diagram showing another state of the shielding portions 29a and 29b of FIG. 4(b). [Figure 8] FIG. [Figure 9] FIG. 2 is a diagram showing a state in which the reflecting member 23 is moved between the optical fibers 21. [Figure 10] FIG. 1A is a plan view showing a state in which the reflecting member 23 has been moved between the optical fibers 21, and FIG. [Figure 11] FIG. 4A is a diagram showing a step of performing focus adjustment, and FIG. 4B is a diagram showing a step of performing rotational alignment. [Figure 12] 1A is a diagram showing a state in which the reflecting member 23 is retracted, and FIG. 1B is a diagram showing a process of fusing the optical fibers 21 together. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a perspective view showing a fusion splicer 1. The fusion splicer 1 includes a holder placement section 11 on which a holder for holding an optical fiber is placed, an optical fiber holding section 5 in which the optical fiber is arranged, a cover section 3, an operation section 15 for operating the fusion splicer 1, a display section 17 for displaying various information, etc. The operation section 15 and the display section 17 may be integrated by making the display section 17 a touch panel.

[0028] The optical fibers are held in a V-groove on the optical fiber holding part 5. A pair of electrodes 7 are disposed facing each other in a direction substantially perpendicular to the facing direction of the pair of optical fibers. The lid part 3 is rotatable around a rotation axis 9. A clamp 13 is provided on the back surface of the lid part 3, and when the lid part 3 is closed, the tip of the clamp 13 is located at a position corresponding to the position of the optical fiber on the optical fiber holding part 5. That is, the pair of optical fibers can be held facing each other in the optical fiber holding part 5 by the clamp 13 provided on the back surface of the lid part 3. An end face imaging part, which will be described later, is built in between the clamps 13, and is located at a position where the vicinity of the tips of the pair of optical fibers can be imaged when the lid part 3 is closed.

[0029] The fusion splicer 1 connects a pair of optical fibers by fusion. The optical fibers are held by a pair of holders (not shown), and the holders are placed on a holder placement unit 11. In this state, the lid unit 3 is closed, and an arc is generated between the pair of electrodes 7 with the tips of the optical fibers butted together, thereby melting and splicing the tips of the optical fibers.

[0030] Fig. 2 is a schematic diagram of the vicinity of the fused portion when the optical fiber is installed, Fig. 3(a) is a side view seen from the axial direction of the optical fiber 21 (Z direction in Fig. 2), and Fig. 3(b) is a side view seen from the axial direction of the electrode 7 (X direction in Fig. 2). Note that Figs. 2, 3(a) and 3(b) show the state in which the reflecting member 23 is retracted.

[0031] 2, in the following description, the opposing direction of the electrodes 7 is the X direction, the opposing direction of the optical fibers 21 which is perpendicular to the X direction is the Z direction, and the direction perpendicular to the X direction and the Z direction (the up and down direction in the figure) is the Y direction. Also, the rotation direction about the Z direction as the rotation axis is the R direction. Also, in the following figures, configurations that are not necessary for the description are omitted.

[0032] As described above, a pair of optical fibers 21 are disposed facing each other. Also, a pair of electrodes 7 are disposed facing each other in a direction perpendicular to the facing direction of the optical fibers 21 (parallel to the X direction). By aligning the tip positions of the optical fibers 21 and generating an arc between the electrodes 7, the optical fibers can be fused together.

[0033] An end face imaging section 19a is disposed above the opposing portions of the optical fibers 21, and a first side imaging section 19b and a second side imaging section 19c are disposed below them. The end face imaging section 19a, the first side imaging section 19b, and the second side imaging section 19c can image the tip positions of the pair of optical fibers 21 from a direction (side surface) substantially perpendicular to the opposing direction of the optical fibers 21. Furthermore, the first side imaging section 19b and the second side imaging section 19c can image the tip positions of the optical fibers 21 from, for example, two different directions that are perpendicular to each other.

[0034] The reflecting member 23 and the end face imaging section 19a are disposed in the up-down direction (Y direction in FIG. 2) of the optical fiber 21 so as to face each other. In the illustrated example, the reflecting member 23 is disposed on the lower side (the side of the first side imaging section 19b and the second side imaging section 19c) and the end face imaging section 19a is disposed on the upper side (the side of the lid section 3, not shown), but the opposite is also possible. Also, the end face imaging section 19a and the reflecting member 23 do not have to be positioned to face each other.

[0035] As shown in Fig. 3(b), the reflecting member 23 has reflecting surfaces 27a and 27b. The reflecting surfaces 27a and 27b are arranged facing in opposite directions, and can each reflect light incident from, for example, the Z direction in a direction at 90 degrees (upward in the Y direction). When a pair of optical fibers 21 are arranged opposite to each other, the reflecting member 23 can be moved between the optical fibers 21 by a drive unit (Y direction in the figure). The end face imaging unit 19a can capture an image reflected by the reflecting member 23.

[0036] In a state where the reflecting member 23 is retracted from the position facing the optical fiber 21, the reflecting member 23 is covered by the shielding member 25. That is, when the reflecting member 23 is in the retracted state, the shielding member 25 is disposed between the reflecting member 23 and the optical fiber 21 (fused portion) side. The shielding member 25 can be opened and closed in accordance with the vertical movement of the reflecting member 23.

[0037] Fig. 4 is a perspective view showing the structures of the reflecting member 23 and the shielding member 25, Fig. 5(a) is a front view in the X direction showing the shielding member 25 in a closed state, and Fig. 5(b) is a front view in the X direction showing the shielding member 25 in an open state. As described above, in a state in which the reflecting member 23 is retracted from the position facing the optical fiber 21, the shielding member 25 is disposed so as to cover the upper side of the reflecting member 23 (between the reflecting member 23 and the optical fiber 21). The pair of shielding members 25 maintain a closed state with their tips butted against each other by an elastic member such as a coil spring (not shown), for example.

[0038] Rotating parts 35 are formed at the bottom of the shielding members 25, and the shielding members 25 can be opened and closed by rotating the rotating parts 35. At this time, a tapered part 33 is formed at the bottom of the shielding members 25 in a direction gradually moving away from the rotating parts 35 as it approaches the tip of the shielding members 25. Also, a pin 31 is disposed at the bottom of the reflecting member 23. The back side of FIG. 5(a) has the same structure.

[0039] 5(b), when the reflecting member 23 is raised toward between the optical fibers 21 (arrow A in the figure), the pin 31 of the reflecting member 23 comes into contact with the tapered portion 33, and the shielding members 25 are pushed apart (arrow B in the figure). That is, the shielding members 25 rotate in opposite directions about the rotating portion 35 as the rotation axis, and the upper portions open, so that they do not interfere with the rising reflecting member 23.

[0040] When the reflecting member 23 rises to between the opposing portions of the optical fibers 21, the upward movement stops. In this way, when the reflecting member 23 moves to a position opposing the optical fibers 21, the shielding member 25 opens in conjunction with the reflecting member 23. Similarly, when the shielding member 25 is lowered, the shielding member 25 returns to the closed state again by the force of the elastic member described above. That is, when the reflecting member 23 retreats from the position opposing the optical fibers 21, the shielding member 25 closes in conjunction with the movement of the reflecting member 23. Note that the opening and closing mechanism for the shielding member 25 is not limited to this example, and any mechanism may be used as long as it can open and close in conjunction with the movement of the reflecting member 23 when the reflecting member 23 rises and falls.

[0041] 4, the shielding members 25 each have a wall portion 26 on one side, and shielding portions 29a, 29b on the upper portion. The wall portion 26 is not formed on the side surface of the shielding member 25 in the opening / closing direction (Z direction), but is formed on a side surface (X direction) different from the opening / closing direction of the shielding member 25. By not forming the wall portion 26 on the side surface of the shielding member 25 in the opening / closing direction in this way, it is possible to avoid interference with other members (e.g., the optical fiber holding part 5, etc.) that are arranged in the opening direction when the shielding member 25 is opened.

[0042] Furthermore, when the shielding members 25 are closed, the upper shielding portions 29a, 29b butt against each other, and the internal reflecting member 23 can be shielded from the optical fiber 21, the electrode 7, and the like above.

[0043] Fig. 6(a) is a conceptual diagram showing the state of the shielding parts 29a, 29b at part C in Fig. 5(a). In this embodiment, when the shielding member 25 is closed, the tip part (shielding parts 29a, 29b) of the shielding member 25 has a convex shape facing upward (towards the opposing position of the optical fiber 21). In this way, when the shielding member 25 is opened, it is possible to prevent the shielding parts 29a, 29b from interfering with other members (e.g., the optical fiber holding part 5, etc.) arranged in the opening direction. In this way, by appropriately selecting the formation direction of the wall part 26 and the shapes of the shielding parts 29a, 29b, it is possible to allow the opening and closing operation of the shielding member 25 in an extremely narrow space.

[0044] As described above, when the shielding member 25 is closed, the shielding portions 29a, 29b butt against each other and cover the upper side of the lower reflecting member 23, and when the shielding member 25 is opened, the reflecting member 23 can move upward from between the shielding portions 29a, 29b as shown in Fig. 6(b). On the other hand, in this configuration, if a small gap is formed between the mating surfaces of the shielding portions 29a, 29b in the closed state, there is a risk that foreign matter or the like may enter the internal reflecting member 23 (reflecting surfaces 27a, 27b) from above through the gap.

[0045] For this reason, as shown in Fig. 7(a), when the shielding parts 29a, 29b are butted against each other and the shielding member 25 is closed, it is desirable that the tips (shielding parts 29a, 29b) of the pair of shielding members 25 overlap (D in the figure) in a plan view (as viewed from above in the Y direction). By doing so, even if a small gap is formed between the shielding parts 29a, 29b, it is possible to prevent foreign matter that has fallen from above from entering the inside. Even in this case, as shown in Fig. 7(b), when the shielding member 25 is opened, the shielding member 25 can be raised from between the shielding parts 29a, 29b.

[0046] In addition, by repeatedly discharging in the fusion machine 1, oxygen molecules in the windshield are dissociated by the discharge and recombined with other oxygen molecules, generating ozone. Since ozone has a strong oxidizing power, it is desirable to use a material with high corrosion resistance for the shielding member 25. In addition, since the discharge for fusion has a heat quantity that is enough to melt glass, heat resistance and mechanical strength are also required. For this reason, the material for the shielding member 25 is desirably a metal, and among them, it is preferable to use austenitic stainless steel, which has high corrosion resistance. More specifically, SUS304, SUS312, SUS316, etc. can be used for the shielding member 25 (wall portion 26, shielding portions 29a, 29b).

[0047] Next, the configuration of the fusion splicer 1 will be described. As shown in Fig. 8, the fusion splicer 1 includes an imaging section (end face imaging section 19a, first side imaging section 19b, second side imaging section 19c), an alignment drive section (first movement drive section 44, second movement drive section 45, rotation drive section 42), a transport drive section 43, a reflecting member lift drive section 41, a control section 40 that controls these sections, a display section 17, etc. Note that configurations such as discharge control that are not necessary for the description of this embodiment will be omitted.

[0048] The operation unit 15 (see FIG. 1) can input various control contents and setting conditions performed by the control unit 40. The display unit 17 can display images captured by the imaging unit, information such as fusion conditions, etc. The alignment drive unit can move the optical fiber 21 (the optical fiber holding unit 5 and the holder placement unit 11) in the X, Y, and R directions shown in FIG. 2. For example, the first movement drive unit 44 and the second movement drive unit 45 can align the optical fiber 21 by moving at least one of a pair of optical fibers in different directions perpendicular to the axial direction. That is, the first movement drive unit 44 and the second movement drive unit 45 can align the optical fiber 21 in the X direction and the Y direction.

[0049] Furthermore, the rotation drive unit 42 can align the pair of optical fibers in the circumferential direction by rotating at least one of the pair of optical fibers about an axis in the opposing direction of the pair of optical fibers. Each alignment drive unit may be disposed for only one of the optical fiber holding units 5, or may be disposed for both of the pair of optical fiber holding units 5. For example, the first movement drive unit 44 and the second movement drive unit 45 (i.e., X- and Y-direction alignment) may be disposed for only one of the optical fibers, and the rotation drive unit 42 may be disposed for both of the optical fibers.

[0050] Furthermore, the transport drive unit 43 can transport each of the opposing optical fibers 21 individually in the axial direction (Z direction) of the optical fibers 21. The reflecting member lift drive unit 41 can move the reflecting member 23 in the up and down direction (Y direction). Each drive unit is operated by, for example, a motor or the like.

[0051] Next, a method for aligning the optical fiber 21 will be described. The alignment work of the tip position (XY direction) of the optical fiber 21 can be performed by a conventional method. For example, the tip position of the optical fiber 21 is imaged from each direction by the first side imaging unit 19b and the second side imaging unit 19c and displayed on the display unit 17, and the first movement drive unit 44 and the second movement drive unit 45 are operated using the operation unit 15 (the position and orientation of the optical fiber holding unit 5 and the holder placement unit 11 are operated) so that the XY positions of the optical fiber 21 and the holder placement unit 11 are aligned, thereby enabling alignment of the optical fiber 21 in the X direction and the Y direction.

[0052] In the case of connecting single-core optical fibers, the alignment work is completed by only XY alignment. On the other hand, in the case of aligning a multicore fiber or a polarization-maintaining fiber in which the arrangement of the cores in the cross section has a circumferential direction, alignment is required not only in the XY directions of the optical fiber 21 but also in the rotational direction R. For this reason, in the present invention, a reflecting member 23 and an end face imaging unit 19a capable of observing the end face of the optical fiber 21 are used.

[0053] A method for aligning the rotation direction R will be described below. The operation of each of the following parts is controlled by the control unit 40, either automatically or via input from the operation unit 15. Fig. 9 is a diagram showing a state in which the reflecting member 23 is raised and the reflecting surfaces 27a, 27b are disposed between the optical fibers 21. At this time, a gap is formed between the optical fibers 21 to an extent that the reflecting member 23 can be inserted. This gap can be formed by moving the optical fibers 21 axially backward by the transport drive unit 43.

[0054] Fig. 10(a) is a view of the state of Fig. 9 as seen from the end face imaging unit 19a side, and Fig. 10(b) is an enlarged view of part G of Fig. 10(a). As described above, the reflecting member 23 has reflecting surfaces 27a, 27b in the direction of each optical fiber 21. In addition, a groove 24 is formed in the surface of the reflecting member 23 facing the electrode 7 in a direction substantially parallel to the moving direction of the reflecting member 23. For example, when the reflecting member 23 is composed of a mirror having reflecting surfaces 27a, 27b and a holder that holds the mirror, the groove 24 can be formed by making a cut in the portion of the holder that faces the electrode 7.

[0055] The electrodes 7 are arranged at an interval suitable for fusion, for example, without having a driving mechanism for changing the interval. In this way, by forming an interference prevention groove 24 at a position of the reflecting member 23 facing the electrode 7, it is possible to prevent interference between the electrode 7 and the reflecting member 23. Similarly, by forming grooves on the reflecting surfaces 27a and 27b sides of the holder, it is possible to ensure the reflecting areas of the reflecting surfaces 27a and 27b. In other words, it is desirable to hold only the vicinity of the four corners of the mirror with the holder.

[0056] Here, it is desirable that the opening and closing direction of the shielding member 25 (Z direction in Fig. 9 and Fig. 10(a)) is different from the arrangement direction of the first side imaging unit 19b and the second side imaging unit 19c that capture images of the alignment position of the optical fiber 21 (the direction in which the first side imaging unit 19b and the second side imaging unit 19c are arranged side by side, that is, the X direction in Fig. 10). By doing so, it is possible to prevent foreign matter, etc., adhering to the upper surface of the shielding member 25 from falling onto the first side imaging unit 19b and the second side imaging unit 19c when the shielding member 25 is opened and closed.

[0057] 11(a), an image of the optical fiber 21 obtained by the reflecting member 23 is captured by the end face imaging unit 19a. At this time, by irradiating light from the opposite end face or side face of the optical fiber 21, the arrangement of the cores, etc. on the end face can be clearly imaged.

[0058] As described above, the reflecting member 23 has a first reflecting surface 27a that reflects an image of the end face of one optical fiber 21 toward the end face imaging section 19a (arrow I in the figure), and a second reflecting surface 27b that reflects an image of the end face of the other optical fiber 21 toward the end face imaging section 19a (arrow H in the figure). Therefore, the end faces of one optical fiber 21 and the other optical fiber 21 can be simultaneously imaged by the end face imaging section 19a.

[0059] In this embodiment, the reflection direction of the image of the end face of one optical fiber 21 on the reflection surface 27a is the same as the reflection direction of the image of the end face of the other optical fiber 21 on the reflection surface 27b. Therefore, the end faces of the optical fibers 21 can be simultaneously imaged by one end face imaging section 19a. In this case, the imaging range of the end face imaging section 19a can be set to more than twice the outer diameter of the optical fiber 21 (a range in which the end faces of a pair of optical fibers 21 can be imaged side by side, taking into consideration the spread of the image from the end face of the optical fiber 21 to the end face imaging section 19a).

[0060] On the other hand, the reflection direction of the image of the end face of one optical fiber 21 on the reflecting surface 27a and the reflection direction of the image of the end face of the other optical fiber 21 on the reflecting surface 27b may be different directions, and the end faces of the respective optical fibers 21 may be simultaneously imaged by the multiple end face imaging units 19a. In this case, the imaging range of each end face imaging unit 19a can be made small. That is, it is sufficient to have one or multiple end face imaging units 19a capable of imaging the image reflected by the reflecting member 23. However, when performing alignment in the rotational direction, it is desirable to simultaneously image the end faces of a pair of optical fibers 21 by one end face imaging unit 19a in order to reduce the influence of machine differences and the like.

[0061] Here, the focus adjustment of the end face of each optical fiber 21 is performed by moving each optical fiber 21 in the axial direction (arrows J and K in the figure). As described above, when fusing the optical fibers 21, in order to butt the optical fibers 21 together and to perform screening after fusing, a conveying drive unit 43 is provided for moving the optical fibers 21 in the axial direction. Therefore, in this embodiment, the focus adjustment of each end face can be performed by moving the optical fibers 21 in the Z direction by this conveying drive unit 43.

[0062] More specifically, the control unit 40 can automatically or manually operate the transport drive unit 43 corresponding to each optical fiber 21 to adjust the focus of the captured image of each optical fiber 21. When adjusting the focus in the end face imaging unit 19a, it is necessary to adjust, for example, the position of the end face imaging unit 19a itself or the position of a lens (not shown) so that the end face images of each optical fiber 21 are simultaneously in focus. However, by controlling the transport drive unit 43 by the control unit 40 to control the focal position of the captured image in the end face imaging unit 19a, the end face images of each optical fiber 21 can be simultaneously acquired in real time by the end face imaging unit 19a, so that the focus adjustment can be performed simultaneously and individually for each optical fiber 21.

[0063] As shown in FIG. 11(b), after the focus adjustment is completed, alignment in the rotation direction R is performed using the obtained image (in the directions of arrows L and M in the figure). As described above, the end face imaging unit 19a can simultaneously acquire end face images of each optical fiber 21 in real time. For this reason, the control unit 40 can automatically or manually align the rotation direction R of each optical fiber 21 by individually controlling the operation of the rotation drive units 42 corresponding to each optical fiber 21. In other words, the alignment drive units can align the pair of optical fibers in the rotation direction by rotating at least one of the pair of optical fibers 21 around an axis that is the opposing direction of the pair of optical fibers 21.

[0064] The control unit 40 can also automatically control the amount of rotation of the optical fiber 21 by the rotation drive unit 42 based on the image captured by the end face imaging unit 19a. For example, the image obtained by the end face imaging unit 19a may be binarized by the image processing unit 48 to identify the arrangement of the cores, etc., and the calculation processing unit 49 may calculate rotation angle information so that the positions of the cores, etc. of both are the same, and the control unit 40 may drive the rotation drive unit 42 based on the obtained rotation angle information.

[0065] After the alignment in the rotation direction R is completed, the reflecting member 23 is lowered downward (arrow N in the figure) as shown in Fig. 12(a). That is, the reflecting member 23 is set in the retracted state. At this time, in conjunction with the retracting movement of the reflecting member 23, the shielding member 25 is closed by an elastic member or the like (not shown).

[0066] After the alignment work is completed, as shown in Fig. 12(b), the conveyor drive unit 43 is operated to butt the tips of the optical fibers 21 together (arrow O in the figure). Then, an arc is generated between the electrodes 7 under predetermined conditions to perform the fusion work. In this way, the optical fibers 21 can be aligned and spliced ​​together.

[0067] Here, a sensor 46 (see FIG. 8) capable of detecting the state of the reflecting member 23 or the shielding member 25 may be provided. For example, when the sensor 46 detects a state in which the reflecting member 23 is retracted from the position facing the optical fiber or a state in which the shielding member 25 is closed, the control unit 40 enables discharge between the electrodes 7. In this way, by providing a protection mechanism that prohibits the start of discharge unless the retracted state of the reflecting member 23 or the closed state of the shielding member 25 is detected, it is possible to prevent discharge from being erroneously started in a state in which the reflecting member 23 is not shielded.

[0068] Furthermore, when shielding member 25 is closed, the shortest distance between electrode 7 and shielding member 25 (distance F in FIG. 3(a)) is preferably longer than the distance between electrodes 7 (distance E in FIG. 3(a)), and more preferably is at least twice as long. In this way, leakage discharge can be avoided when discharging between electrodes 7.

[0069] As described above, according to this embodiment, the end faces of the pair of optical fibers 21 can be imaged simultaneously, which makes the alignment work easy. Also, by reflecting the images of the respective end faces in the same direction, the end faces of the pair of optical fibers 21 can be imaged by the same end face imaging unit 19a. Also, since the shielding member 25 closes in conjunction with the retreat of the reflecting member 23, there is no need to separately dispose an elevation drive unit for the reflecting member 23 and an opening / closing drive unit for the shielding member 25, and the reflecting member 23 can be reliably shielded by the shielding member 25 when the reflecting member 23 is retreated.

[0070] In this case, by using a sensor 46 capable of detecting a state in which the reflecting member 23 is retracted from the position facing the optical fiber 21 or a state in which the shielding member 25 is closed, it is possible to prevent discharge from occurring when the reflecting member 23 is not shielded due to malfunction, etc.

[0071] Moreover, by opening the shielding member 25 without providing the wall portion 26 that covers the entire side surface in the opening / closing direction, it is possible to avoid interference with the optical fiber holding part 5, etc. Similarly, by making the shielding parts 29a, 29b into an upwardly facing convex shape (mountain shape), it is possible to avoid interference with the optical fiber holding part 5, etc. when the shielding member 25 is opened.

[0072] Furthermore, by setting the opening and closing direction of the shielding member 25 to a direction different from the arrangement direction of the first lateral imaging section 19b and the second lateral imaging section 19c that image the alignment position of the optical fiber 21, it is possible to prevent foreign objects, etc. from falling onto the first lateral imaging section 19b or the second lateral imaging section 19c when the shielding member 25 is opened or closed.

[0073] Furthermore, by making parts of shielding portions 29a, 29b overlap each other in a planar view when shielding member 25 is closed, even if a small gap is formed at the butt joint of shielding portions 29a, 29b, it is possible to prevent foreign matter and the like from entering inside shielding member 25.

[0074] In addition, by grasping the position of the end face of the optical fiber 21 in the image captured by the end face imaging unit 19a, it is also possible to perform alignment in the XY directions only by observing the end face with the end face imaging unit 19a. In other words, since the position in the XY directions and the direction of the rotation direction R can be known from the position of the end face of the optical fiber 21 in the captured image, all alignment work can be performed by observing the end face.

[0075] In addition, in observing the end face of the optical fiber 21, the state of the end face of the optical fiber 21 may be grasped. For example, it is possible to grasp from an image of the end face whether there is a break or a crack in a part of the end face. In particular, by grasping the focal depth and the circularity at each part of the end face, it is possible to grasp the end face shape of the optical fiber 21 or an abnormality in the end face shape of the optical fiber 21, such as when the cut surface is oblique or has a concave shape. Furthermore, it is also possible to image the form of the cut surface by grasping the interference fringes of the end surface using an imaging device such as an interference microscope.

[0076] Although the embodiment of the present invention has been described above with reference to the attached drawings, the technical scope of the present invention is not limited to the above-described embodiment. It is clear that a person skilled in the art can think of various modifications or alterations within the scope of the technical ideas described in the claims, and it is understood that these also naturally belong to the technical scope of the present invention. [Explanation of symbols]

[0077] 1. Fusion machine 3……Lid part 5: Optical fiber holder 7……Electrode 9...Rotation axis 11...Holder placement section 13...Clamp 15……Operation unit 17……Display section 19a: End surface imaging section 19b...First side imaging unit 19c...Second lateral imaging unit 21...Optical fiber 23...Reflective member 24……groove 25...Shielding member 26……Wall part 27a, 27b……Reflective surface 29a, 29b……shielding part 31………Pin 33...Tapered section 35...Rotating section 40...Control unit 41... Reflecting member lifting drive unit 42...Rotation drive unit 43...Transport drive unit 44...First moving drive unit 45...Second moving drive unit 46...Sensor 48: Image processing section 49... Processing unit

Claims

1. A fusion splicer for connecting optical fibers, comprising: an optical fiber holding portion that holds a pair of optical fibers facing each other; A pair of electrodes arranged to face each other in a direction substantially perpendicular to the facing direction of the pair of optical fibers; a reflecting member movable between the pair of optical fibers when the pair of optical fibers are disposed opposite each other; an imaging unit that captures an image reflected by the reflecting member; an alignment drive unit that can align the pair of optical fibers by rotating at least one of the pair of optical fibers about an axis in the opposing direction of the pair of optical fibers; Equipped with the reflecting member has a reflecting surface that reflects an image of the end surface of each of the optical fibers toward the imaging unit, a pair of shielding members disposed between the reflecting member and the optical fiber when the reflecting member is retracted from the opposing position of the optical fiber, and configured to close in conjunction with the movement of the reflecting member when the reflecting member is retracted from the opposing position of the optical fiber.

2. 2. The fusion splicer according to claim 1, further comprising a protection mechanism that enables discharge between the electrodes by detecting a state in which the reflective member is retracted from a position facing the optical fiber or a state in which the shielding member is closed, the protection mechanism further comprising a sensor that can detect a state in which the reflective member is retracted from a position facing the optical fiber or a protection mechanism that enables discharge between the electrodes by detecting a state in which the reflective member is retracted from a position facing the optical fiber or a state in which the shielding member is closed.

3. 3. The fusion splicer according to claim 1, wherein no wall is formed on a side surface of the shielding member in a direction in which the shielding member opens, and a wall is formed on a side surface of the shielding member opposite to the direction in which the shielding member opens.

4. 4. The fusion splicer according to claim 1, wherein when the tip ends of the pair of shielding members are butted against each other in a closed state of the shielding members, a convex shape is formed toward a position where the optical fibers face each other by the pair of tip ends of the shielding members.

5. A fusion splicer as described in any one of claims 1 to 4, characterized in that a pair of lateral imaging units are arranged in a direction different from that of the imaging unit, and the opening and closing direction of the shielding member is a direction different from the arrangement direction of the lateral imaging units that image the alignment position of the optical fiber.

6. 6. The fusion splicer according to claim 1, wherein the shielding members have shielding portions at their tip portions, and when the pair of shielding members are in a closed state, the shielding portions at the tip portions of the shielding members are butted against each other, the butting portions of the shielding portions are formed obliquely with respect to a direction perpendicular to a direction of opening and closing, and parts of the tip portions of the pair of shielding members overlap each other in a plan view.

7. 7. The fusion splicer according to claim 1, wherein the shielding member is made of austenitic stainless steel.

8. 8. The fusion splicer according to claim 1, wherein when the shielding member is closed, the shortest distance between the electrode and the shielding member is longer than the distance between the electrodes.

9. 9. The fusion splicer according to claim 8, wherein when the shielding member is closed, the shortest distance between the electrodes and the shielding member is at least twice the distance between the electrodes.

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