JP7630396B2 - Fusion machine - Google Patents

Description

The present invention relates to a fusion machine with excellent alignment workability.

A fusion splicer is used to connect optical fibers together. The fusion splicer butts together optical fibers held in a pair of holders, places them between electrodes, and uses an arc to fuse the tips of the optical fibers together, thus connecting the optical fibers together.

When fusing optical fibers together, alignment work is required to align the tip positions of the optical fibers. For this reason, conventionally, alignment is 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.

On the other hand, when the optical fiber is not a typical single-core optical fiber but has a circumferential direction relative to the 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 X-Y direction of the optical fiber, but also rotational alignment in the circumferential direction around the axial direction of the optical fiber is required.

To perform such rotational alignment of optical fibers, 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 unit to be imaged, and rotational alignment is performed by observing the end face (for example, Patent Document 1).

JP 2004-53625 A

However, with conventional methods, the reflective surface of the reflective member may become dirty due to discharges or debris flying from the optical fiber, degrading the image quality when observing the end face of the optical fiber. This can make it difficult to achieve accurate alignment.

The present invention was made in consideration of these problems, and aims to provide a fusion machine that allows for highly accurate alignment.

In order to achieve the above-mentioned object, the present invention provides a fusion splicer for connecting optical fibers, comprising an optical fiber holding section for holding a pair of optical fibers facing each other, a pair of electrodes arranged opposite each other in a direction approximately perpendicular to the facing direction of the pair of optical fibers, a reflective member that can move between the optical fibers when the pair of optical fibers is arranged opposite each other, an imaging section for capturing an image reflected by the reflective member, and an alignment drive section that can align 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, wherein the reflective member has a reflective surface that reflects an image of an end face of each of the optical fibers toward the imaging section, and the fusion splicer has a pair of shielding members that are arranged between the reflective member and the optical fibers when the reflective member is retracted from the facing position of the optical fibers, and are configured to close in conjunction with the movement of the reflective member when the reflective member is retracted from the facing position of the optical fibers.

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

A wall portion may not be formed on a side surface of the shielding member in a direction in which the shielding member opens , and a wall portion may be formed on a side surface of the shielding member in a direction different from the direction in which the shielding member opens .

It is desirable that when the tip ends of the pair of shielding members are butted together in a closed state of the shielding members, a convex shape is formed toward the opposing position of the optical fibers by the pair of tip ends of the shielding members.

It is preferable that a pair of side 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 that of the side imaging units that image the alignment position of the optical fiber.

The shielding members have shielding portions at their tip portions, and when the pair of shielding members are closed, the shielding portions at the tip portions of the shielding members are butted together, the butt portions of the shielding portions are formed at an angle with respect to a direction perpendicular to the opening/closing direction, and portions of the tip portions of the pair of shielding members overlap when viewed in a plan view.

The shielding member is preferably made of austenitic stainless steel.

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.

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

In particular, by using a sensor that can detect when the reflective member has been retracted from the position facing the optical fiber or when the shielding member is closed, it is possible to prevent discharge from occurring when the reflective member is not retracted or the shielding member is not closed due to malfunction, etc.

In addition, by not forming a wall on the side of the shielding member in the opening and closing direction, 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.

Similarly, when the shielding member is closed, the tip of the shielding member is convex toward the opposing position of the optical fiber, and the upper end of the shielding member is narrowed, so that when the shielding member is opened, interference with the optical fiber holding part, etc., that is arranged in the opening and closing direction of the shielding member can be prevented.

In addition, by opening and closing the shielding member in a direction different from the arrangement direction of the lateral imaging unit that captures the alignment position of the optical fiber, it is possible to prevent foreign objects from falling onto the lateral imaging unit when the shielding member is opened or closed.

In addition, by making the tips of the pair of shielding members overlap in a plan 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.

In addition, 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.

In addition, when the shielding member is closed, leak discharge to the shielding member can be suppressed by making the shortest distance between the electrode and the shielding member at least twice the distance between the electrodes.

The present invention provides a fusion machine that allows for highly accurate alignment.

FIG. FIG. 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. FIG. 4 is an enlarged perspective view of a reflecting member 23 and a shielding member 25. 1A is a side view of the shielding member 25 in a closed state, and FIG. 1B is a side view of the shielding member 25 in an open state with the reflecting member 23 raised. 5A shows the state of the shielding portions 29a and 29b in FIG. 5A, and FIG. 4B shows the state of the shielding portions 29a and 29b in FIG. 5A is a diagram showing another state of the shielding portions 29a and 29b of FIG. 5A, and FIG. 5B is a diagram showing another state of the shielding portions 29a and 29b of FIG. 4B. FIG. FIG. 13 is a diagram showing a state in which the reflecting member 23 is moved between the optical fibers 21. 4A is a plan view showing a state in which the reflecting member 23 has been moved between the optical fibers 21, and FIG. 4B is an enlarged view of a portion G in FIG. 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. 4A is a diagram showing a state in which the reflecting member 23 is retracted, and FIG. 4B is a diagram showing a process of fusing the optical fibers 21 together.

Below, 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 lid 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.

The optical fiber is held in a V-groove on the optical fiber holding part 5. A pair of electrodes 7 are arranged facing each other in a direction approximately perpendicular to the facing direction of the pair of optical fibers. The lid part 3 can rotate 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. In other words, the clamp 13 provided on the back surface of the lid part 3 can hold the pair of optical fibers facing each other in the optical fiber holding part 5. In addition, an end face imaging part described later is built in between the clamps 13, and when the lid part 3 is closed, it is located at a position where it can image the vicinity of the tips of the pair of optical fibers.

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

Figure 2 is a schematic diagram of the vicinity of the fusion part when the optical fiber is installed, Figure 3(a) is a side view seen from the axial direction of the optical fiber 21 (Z direction in Figure 2), and Figure 3(b) is a side view seen from the axial direction of the electrode 7 (X direction in Figure 2). Note that Figures 2, 3(a), and 3(b) show the state in which the reflective member 23 is retracted.

In the following explanation, as shown in FIG. 2, the opposing direction of the electrodes 7 is the X direction, the opposing direction of the optical fibers 21 that is perpendicular to the X direction is the Z direction, and the direction perpendicular to the X and Z directions (the up and down direction in the figure) is the Y direction. The rotation direction around the Z direction as the rotation axis is the R direction. Also, in the following figures, configurations that are not necessary for the explanation are omitted from the illustration.

As described above, a pair of optical fibers 21 are arranged facing each other. In addition, a pair of electrodes 7 are arranged 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.

The end face imaging unit 19a is arranged above the opposing portions of the optical fibers 21, and the first side imaging unit 19b and the second side imaging unit 19c are arranged below. The end face imaging unit 19a, the first side imaging unit 19b, and the second side imaging unit 19c can image the tip positions of the pair of optical fibers 21 from a direction (side surface) that is approximately perpendicular to the opposing direction of the optical fibers 21. The first side imaging unit 19b and the second side imaging unit 19c can also image the tip positions of the optical fibers 21 from two different directions that are perpendicular to each other, for example.

The reflecting member 23 and the end face imaging unit 19a are arranged 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 arranged on the bottom (the side of the first side imaging unit 19b and the second side imaging unit 19c) and the end face imaging unit 19a is arranged on the top (the side of the lid unit 3, not shown), but the opposite is also possible. Also, the end face imaging unit 19a and the reflecting member 23 do not have to be positioned facing each other.

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 90 degree direction (upward in the Y direction). When a pair of optical fibers 21 are arranged opposite each other, the reflecting member 23 can be moved between the optical fibers 21 by the drive unit (Y direction in the figure). The end face imaging unit 19a can capture an image reflected by the reflecting member 23.

When 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. In other words, 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). The shielding member 25 can be opened and closed in accordance with the vertical movement of the reflecting member 23.

Figure 4 is a perspective view showing the structure of the reflective member 23 and the shielding member 25, Figure 5(a) is a front view in the X direction showing the shielding member 25 in a closed state, and Figure 5(b) is a front view in the X direction showing the shielding member 25 in an open state. As described above, when the reflective member 23 is retracted from the position facing the optical fiber 21, the shielding member 25 is positioned so as to cover the upper part of the reflective member 23 (between the reflective 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).

A rotating portion 35 is formed at the bottom of each shielding member 25, and the shielding member 25 can be opened and closed by rotating the rotating portion 35. At this time, a tapered portion 33 is formed at the bottom of the shielding member 25, which gradually moves away from the rotating portion 35 as it approaches the tip of the shielding member 25. In addition, a pin 31 is disposed at the bottom of the reflecting member 23. The rear side of FIG. 5(a) also has a similar structure.

As shown in FIG. 5(b), when the reflecting member 23 is raised toward the gap 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). In other words, the shielding members 25 rotate in opposite directions around the rotating portion 35 as the rotation axis, opening their upper portions, so they do not interfere with the rising reflecting member 23.

When the reflecting member 23 rises to between the opposing portions of the optical fiber 21, the rising motion stops. In this way, when the reflecting member 23 moves to a position opposing the optical fiber 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 a closed state again due to the force of the elastic member described above. In other words, when the reflecting member 23 retreats from the position opposing the optical fiber 21, the shielding member 25 closes in conjunction with the movement of the reflecting member 23. Note that the opening and closing mechanism of 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.

As shown in FIG. 4, each shielding member 25 has a wall portion 26 on one side and shielding portions 29a, 29b on the top. 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. In this way, by not forming the wall portion 26 on the side surface of the shielding member 25 in the opening/closing direction, it is possible to avoid interference with other members (e.g., optical fiber holding portion 5, etc.) that are arranged in the opening direction when the shielding member 25 is opened.

When the shielding members 25 are closed, the upper shielding parts 29a and 29b butt together, shielding the internal reflective member 23 from the optical fiber 21 and electrode 7 above.

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

As described above, when the shielding member 25 is closed, the shielding portions 29a and 29b butt together 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 and 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 and 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 and 27b) from above through the gap.

For this reason, as shown in FIG. 7(a), when the shielding portions 29a, 29b are butted together and the shielding member 25 is closed, it is desirable that the tips (shielding portions 29a, 29b) of the pair of shielding members 25 overlap (D in the figure) in a plan view (when viewed from above in the Y direction). By doing so, even if a small gap is formed between the shielding portions 29a, 29b, it is possible to prevent foreign matter that falls 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 portions 29a, 29b.

In addition, by repeatedly discharging in the fusion machine 1, oxygen molecules in the windshield are dissociated by the discharge and recombine with other oxygen molecules, generating ozone. Because ozone has a strong oxidizing power, it is desirable to use a material with high corrosion resistance for the shielding member 25. In addition, because the discharge for fusion has a heat quantity that is enough to melt glass, heat resistance and mechanical strength are also necessary. For this reason, metal is desirable as the material for the shielding member 25, 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).

Next, the configuration of the fusion machine 1 will be described. As shown in FIG. 8, the fusion machine 1 is composed of an imaging section (end surface 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, 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.

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 and information such as fusion conditions. The alignment drive unit can move the optical fiber 21 (the optical fiber holding unit 5 and the holder mounting 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 and Y directions.

Furthermore, the rotation drive unit 42 can circumferentially align the pair of optical fibers by rotating at least one of the pair of optical fibers around an axis in the opposing direction of the pair of optical fibers. Each alignment drive unit may be arranged only for one of the optical fiber holding units 5, or may be arranged 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 arranged only for one of the optical fibers, and the rotation drive unit 42 may be arranged for both optical fibers.

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.

Next, a method for aligning the optical fiber 21 will be described. The alignment work for the tip position (X-Y 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 mounting unit 11 are operated) so that the positions of the two are aligned, and the optical fiber 21 can be aligned in the X and Y directions by aligning the X-Y positions of both.

When connecting single-core optical fibers, the alignment process can be completed with just XY alignment. On the other hand, when aligning a multicore fiber or polarization-maintaining fiber, which have a circumferential direction relative to the arrangement of the cores in the cross section, alignment is required not only in the XY directions of the optical fiber 21, but also in the rotational direction R. For this reason, the present invention uses a reflecting member 23 and an end face imaging unit 19a that can observe the end face of the optical fiber 21.

The 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. Figure 9 is a diagram showing the state in which the reflecting member 23 is raised and the reflecting surfaces 27a, 27b are positioned between the optical fibers 21. At this time, a gap is formed between the optical fibers 21 large enough to allow the reflecting member 23 to be inserted. This gap can be formed by moving the optical fibers 21 axially backward using the transport drive unit 43.

Figure 10(a) is a view of the state of Figure 9 from the end face imaging unit 19a side, and Figure 10(b) is an enlarged view of part G of Figure 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 on the surface of the reflecting member 23 facing the electrode 7 in a direction approximately parallel to the movement direction of the reflecting member 23. For example, if the reflecting member 23 is composed of a mirror having reflecting surfaces 27a, 27b and a holder that holds it, the groove 24 can be formed by making a cut in the part of the holder that faces the electrode 7.

The electrodes 7 do not have a driving mechanism for changing the spacing, for example, and are arranged at a spacing suitable for fusion. In this way, by forming an interference prevention groove 24 at a position of the reflecting member 23 facing the electrode 7, interference between the electrode 7 and the reflecting member 23 can be avoided. Similarly, by forming grooves on the reflecting surfaces 27a and 27b of the holding part, the reflecting area of the reflecting surfaces 27a and 27b can be ensured. In other words, it is desirable to hold only the areas near the four corners of the mirror with the holding part.

Here, it is desirable that the opening and closing direction of the shielding member 25 (Z direction in Figs. 9 and 10(a)) is different from the arrangement direction of the first side imaging unit 19b and the second side imaging unit 19c that image 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.

Next, as shown in FIG. 11(a), the 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. at the end face can be clearly imaged.

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

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 each optical fiber 21 can be imaged simultaneously by one end face imaging unit 19a. In this case, the imaging range of the end face imaging unit 19a can be more than twice the outer diameter of the optical fiber 21 (the range in which the end faces of a pair of optical fibers 21 can be imaged side by side, taking into account the spread of the image from the end face of the optical fiber 21 to the end face imaging unit 19a).

In contrast, 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 each optical fiber 21 may be simultaneously imaged by multiple end face imaging units 19a. In this case, the imaging range of each end face imaging unit 19a can be made smaller. In other words, it is sufficient to have one or more end face imaging units 19a that can capture 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 with one end face imaging unit 19a in order to reduce the influence of machine differences, etc.

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, a conveying drive unit 43 is provided for moving the optical fibers 21 in the axial direction in order to butt the optical fibers 21 together and perform screening after fusing. 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.

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 focus adjustment can be performed simultaneously and individually for each optical fiber 21.

As shown in FIG. 11(b), after the focus adjustment is completed, the obtained image is used to align the rotation direction R (in the direction of the 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. Therefore, 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 unit 42 corresponding to each optical fiber 21. In other words, the alignment drive unit can align the rotation direction of the pair of optical fibers 21 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.

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 can be binarized by the image processing unit 48 to identify the arrangement of the cores, etc., and the calculation processing unit 49 can calculate rotation angle information so that the positions of both cores, etc. are the same, and the control unit 40 can drive the rotation drive unit 42 based on the obtained rotation angle information.

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). In other words, the reflecting member 23 is in a retracted state. At this time, in conjunction with the retraction movement of the reflecting member 23, the shielding member 25 is closed by an elastic member or the like (not shown).

After the alignment process is complete, 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 specified conditions to perform the fusion process. In this way, the optical fibers 21 can be aligned and connected.

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 that the reflecting member 23 has been retracted from the position facing the optical fiber or that the shielding member 25 has been 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.

In addition, when the shielding member 25 is closed, the shortest distance between the electrode 7 and the shielding member 25 (distance F in FIG. 3(a)) is preferably longer than the distance between the 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 the electrodes 7.

As described above, according to this embodiment, the end faces of a pair of optical fibers 21 can be imaged simultaneously, making alignment easy. In addition, by reflecting the images of each end face in the same direction, the end faces of a pair of optical fibers 21 can be imaged by the same end face imaging unit 19a. In addition, since the shielding member 25 closes in conjunction with the retraction of the reflecting member 23, there is no need to separately arrange the lifting and lowering drive unit for the reflecting member 23 and the opening and 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 retracted.

In this case, by using a sensor 46 that can detect when the reflecting member 23 is retracted from the position facing the optical fiber 21 or when 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.

In addition, by opening the shielding member 25 without providing a wall portion 26 that covers the entire side surface in the opening/closing direction, interference with the optical fiber holding portion 5, etc. can be avoided. Similarly, by making the shielding portions 29a and 29b into an upwardly facing convex shape (mountain shape), interference with the optical fiber holding portion 5, etc. can be avoided when the shielding member 25 is opened.

In addition, by opening and closing the shielding member 25 in a direction different from the arrangement direction of the first lateral imaging unit 19b and the second lateral imaging unit 19c, which image the alignment position of the optical fiber 21, it is possible to prevent foreign objects, etc. from falling onto the first lateral imaging unit 19b or the second lateral imaging unit 19c when the shielding member 25 is opened or closed.

In addition, by making the shielding portions 29a and 29b overlap in a plan view when the shielding member 25 is closed, even if a small gap is formed at the butt joint between the shielding portions 29a and 29b, it is possible to prevent foreign matter from entering the inside of the shielding member 25.

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 X-Y directions simply by observing the end face with the end face imaging unit 19a. In other words, since the position in the X-Y directions and the direction of rotation 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.

In addition, in observing the end face of the optical fiber 21, it may be possible to grasp the condition of the end face of the optical fiber 21. For example, it is possible to grasp from an image of the end face whether there is a chip or a crack in a part of the end face. In particular, by grasping the focal depth and circularity of 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 possible to image the shape of the cut surface by grasping the interference fringes of the end surface using an imaging device such as an interference microscope.

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-mentioned embodiment. It is clear that a person skilled in the art can come up with various modified or revised examples within the scope of the technical ideas described in the claims, and it is understood that these also naturally fall within the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1... Fusion splicer 3... Cover section 5... Optical fiber holding section 7... Electrode 9... Rotating shaft 11... Holder placement section 13... Clamp 15... Operation section 17... Display section 19a... End face imaging section 19b... First side imaging section 19c... Second side imaging section 21... Optical fiber 23... Reflecting member 24... Groove 25... Shielding member 26... Wall sections 27a, 27b... Reflecting surfaces 29a, 29b... Shielding section 31... Pin 33... Tapered section 35... Rotating section 40... Control section 41... Reflecting member lifting/lowering drive section 42... Rotation drive section 43... Transport drive section 44... First movement drive section 45... Second movement drive section 46... Sensor 48... Image processing section 49... Calculation processing section

Claims (9)

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 along which the pair of optical fibers face each other;
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. The fusion splicer according to claim 1, characterized in that it has a sensor capable of detecting the state of the reflecting member or the shielding member, and has a protection mechanism that enables discharge between the electrodes when the sensor detects that the reflecting member has been retracted from the position facing the optical fiber or that the shielding member has been closed. 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. 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. The fusion splicer according to claim 1, wherein a pair of side imaging units are arranged in a direction different from that of the imaging unit, and a direction in which the shielding member is opened and closed is a direction different from a direction in which the side imaging units that image the alignment position of the optical fiber are arranged. 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. The fusion machine according to any one of claims 1 to 6, characterized in that the shielding member is made of austenitic stainless steel. The fusion machine according to any one of claims 1 to 7, characterized in that when the shielding member is closed, the shortest distance between the electrode and the shielding member is longer than the distance between the electrodes. The fusion machine according to claim 8, characterized in that, when the shielding member is closed, the shortest distance between the electrode and the shielding member is at least twice the distance between the electrodes.

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