JP7773307B2 - Fusion splicer and optical fiber fusion method - Google Patents

Description

The present invention relates to a fusion splicer for connecting optical fibers and a method for fusing optical fibers using the same.

A fusion splicer is used to connect optical fibers together. The fusion splicer uses one or more pairs of electrode rods as a heat source to melt the optical fibers. Glass optical fibers held in a pair of holders are butted together and placed between the electrodes. A high voltage is applied between the tips of the electrodes, generating an aerial discharge that fuses the optical fibers together (see, for example, Patent Document 1).

Japanese Patent Application Laid-Open No. 2004-184543

Figure 8 is a perspective view showing a typical fusion splicer 100 for connecting a pair of optical fibers by fusion. The fusion splicer 100 is equipped with a holding member 103 for positioning the tips of the optical fibers and the electrodes. The holding member 103 has V-grooves formed in mutually perpendicular directions, and a pair of electrode rods 101 are placed in one of the V-grooves and fixed in place by a fixed lid 107. The fixed lid 107 serves as a power supply for the electrode rods 101.

A pair of holder mounting portions 105 are provided facing each other, sandwiching the holding member 103. A holder (not shown) that holds an optical fiber is mounted on the holder mounting portion 105. By holding the optical fiber with the pair of holders and mounting the holder on the holder mounting portion 105, the tip of the optical fiber can be positioned in the other V-groove of the holding member 103 (the V-groove oriented perpendicular to the V-groove in which the electrode rod 101 is positioned). In this way, with the tips of the optical fibers butted together, an arc is generated between the pair of electrode rods 101, melting the tips of the optical fibers and splicing the optical fibers together.

Figure 9(a) is a conceptual diagram showing an optical fiber 109 placed between a pair of electrode rods 101. The tip of the electrode rod 101 is generally conical. When a high voltage is applied to the electrode rods 101, an aerial discharge occurs between the apexes of the cone. By placing the optical fiber 109 in the discharge area 111 obtained in this way, the optical fiber 109 can be reliably melted and connected.

However, repeated fusion splicing of the optical fiber 109 can cause solidified glass vapor from the optical fiber 109 or oxides of the material that makes up the electrode rod 101 to accumulate at the tip of the electrode rod 101. When foreign matter accumulates near the tip of the electrode rod 101 or when wear occurs near the tip of the electrode rod 101, air discharge can occur at points other than the apex of the cone shape.

Figure 9(b) is a conceptual diagram showing the discharge state in this state. If the point at which the air discharge occurs shifts, the position and shape of the discharge part 111 will change from what was designed. This can cause the heating temperature and heating temperature distribution to change and become asymmetric, which can lead to the optical fiber 109 not melting uniformly and can increase the optical connection loss at the fusion splice.

To solve these problems, it was previously necessary to frequently clean and remove foreign matter formed by solidified glass vapor that had adhered to the tip of the electrode rod 101, as well as oxides from the electrode rod material. In some cases, it was also necessary to frequently replace the electrode rod 101 with a new one. However, such replacement and maintenance work reduced the efficiency of the optical fiber connection work.

The present invention was made in consideration of these problems, and aims to provide a fusion machine etc. that can reduce the frequency of cleaning and replacing deposits on electrode rods.

In order to achieve the above-mentioned object, the first invention is a fusion splicer that connects optical fibers arranged opposite each other, and includes at least a pair of electrode rods arranged in a direction perpendicular to the optical fibers, and a rotation drive unit that can rotate at least one of the electrode rods around an axis of rotation in the approximate axial direction of the electrode rods, and with the optical fibers arranged opposite each other on a holding member, the fusion splicer discharges electricity while rotating the electrode rods multiple times , thereby fusing the optical fibers together.

The pair of electrode rods may each be rotatable by the rotary drive unit, and the pair of electrode rods may rotate in the same direction.

The tips of the pair of electrode rods may be located on the rotation axis of the electrode rods .

The rotation speeds of the pair of electrode rods may be different.

The pair of electrode rods may each be rotatable by the rotation drive unit, the rotation axes of the pair of electrode rods may be approximately aligned, the rotation speeds of the pair of electrode rods may be approximately the same, the tip positions of the electrode rods may be positioned 180° out of phase with each other in the direction of rotation, and the pair of electrode rods may rotate while maintaining the relative positional relationship between the tips of the pair of electrode rods .

A V-groove may be formed in the holding member that holds the electrode rod, a bearing may be placed in the V-groove, the electrode rod may be supported by the bearing, and the bearing may be fixed to the holding member by a fixing cover with a positioning portion formed on part of the bearing abutting the end face of the holding member, thereby enabling the electrode rod to be positioned.

The optical fiber may be an optical fiber ribbon in which multiple single-core optical fibers are arranged in parallel.

According to the first invention, even if the discharge origin is not at the tip (center) of the electrode rod, the electrode rod can be rotated during discharge, allowing the discharge origin to rotate around its axis. As a result, when viewed from the optical fiber side, the discharge origin does not remain biased to one side, and the temperature distribution, etc. can be made approximately uniform throughout the entire discharge period. This allows for stable connection quality.

Furthermore, by rotating a pair of electrode rods simultaneously in the same direction, the relative positional relationship between the discharge starting points of the electrode rods can be maintained to a certain extent, and the discharge area can be formed approximately uniformly on the optical fiber throughout the entire discharge period.

Furthermore, by rotating a pair of electrode rods simultaneously in different directions, the relative positions of the discharge starting points of the electrode rods can be changed, allowing the discharge area to be formed approximately uniformly on the optical fiber throughout the entire discharge period.

Furthermore, by varying the rotation speeds of the pair of electrode rods, the relative positional relationship between the discharge starting points of the electrode rods is changed over time, deliberately varying the shape of the discharge area, thereby enabling the discharge area to be formed approximately uniformly relative to the optical fiber throughout the entire discharge period.

Furthermore, by positioning the tip positions of the pair of electrode rods at positions offset from the rotation axis, discharge can be performed at a predetermined angle relative to the axis of the optical fiber. Even in this case, by changing the tip positions of the electrode rods, the discharge area can be formed approximately uniformly relative to the optical fiber throughout the entire discharge period.

Furthermore, by positioning the tip positions of each electrode rod at positions that are 180° out of phase with each other in the direction of rotation, discharge can be carried out so that the center line of the discharge part passes near the center where the optical fiber is installed.

In addition, by abutting a positioning portion formed on part of the bearing placed on the holding member against the rear end surface of the holding member, it is easy to position the electrode rod in the axial direction.

Furthermore, even when the optical fiber is an optical fiber ribbon consisting of multiple parallel single-core optical fibers, the discharge area can be formed approximately uniformly on the optical fiber, preventing a temperature distribution that is biased to one side, and allowing the optical fiber ribbon to be fused with stable quality.

The second invention is a method for fusing optical fibers using the fusion splicer of the first invention, characterized in that the optical fibers are arranged opposite each other on a holding member, and the electrode rod is rotated multiple times while discharging, thereby fusing the optical fibers together.

The optical fiber may be an optical fiber ribbon in which a plurality of single-core optical fibers are arranged in parallel. After the electrode rods are rotated, discharge may be initiated between the electrode rods in this state.

According to the second invention, by rotating the electrode rod during discharge, the discharge starting point is not biased to one side when viewed from the optical fiber side, and the temperature distribution can be made uniform. This allows for stable fusion work.

In addition, when fusing optical fiber ribbons, it is necessary to maintain a roughly uniform temperature distribution for each single optical fiber. However, by rotating the electrode rod, the temperature distribution is not biased to one side, allowing the optical fiber ribbon to be fused with consistent quality.

The present invention provides a fusion machine that can reduce the frequency of cleaning and replacing electrodes with new ones.

4A is a cross-sectional view of the vicinity of the holding member 3, and FIG. 4B is a perspective view of the holding member 3. FIG. 1A is a diagram showing the rotation direction of the electrode rod as viewed from arrow A in FIG. 1A, FIG. 1B is a diagram showing the relationship between time and rotation angle θ, and FIG. 1C is a diagram showing the relationship between time and sin θ. 10A is a diagram showing the relationship between time and another rotation angle θ, and FIG. 10B is a diagram showing the relationship between time and sin θ. 10A is a diagram showing the relationship between time and another rotation angle θ, and FIG. 10B is a diagram showing the relationship between time and sin θ. 1A is another cross-sectional view of the vicinity of the holding member 3, and FIG. 1B is yet another cross-sectional view of the vicinity of the holding member 3. FIG. 1A is a diagram showing the rotation direction of the electrode rod as viewed from arrow A in FIG. 1A, FIG. 1B is a diagram showing the relationship between time and rotation angle θ, and FIG. 1C is a diagram showing the relationship between time and sin θ. 1A and 1B are conceptual diagrams showing the fusion state of the optical fiber ribbon core wire 19, where (a) shows a state in which the tips of the electrode rods 1a and 1b are arranged on the same axis, and (b) and (c) show a state in which the tips of the electrode rods 1a and 1b are misaligned. FIG. 1 is a perspective view showing a fusion splicer 100. 10A and 10B are conceptual diagrams showing the fusion state of the optical fiber 109. FIG.

(First embodiment)
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1(a) is an enlarged cross-sectional view of the vicinity of the electrode rods of a fusion splicer. The overall structure of the fusion splicer is substantially the same as that of the fusion splicer 100 shown in Fig. 8. As described above, the fusion splicer connects a pair of optical fibers arranged opposite each other by fusion, and includes a holding member 3 for positioning and holding the tips of the optical fibers and the electrode rods, and electrode rods 1a, 1b, etc., held by the holding member 3.

Figure 1(b) is a perspective view of the holding member 3. The holding member 3 has V-shaped grooves 13 and 15 formed in directions perpendicular to each other. A pair of electrode rods 1a and 1b are placed in one of the V-shaped grooves 13. In other words, the electrode rods 1a and 1b are arranged on the same axis.

A pair of holder mounting sections (see Figure 8) are provided on either side of the holding member 3, and a holder (not shown) is placed on each holder mounting section. By placing a holder holding an optical fiber on the holder mounting section, the tip of the optical fiber can be positioned facing the V-groove 15 of the holding member 3. In other words, at least a pair of electrode rods 1a, 1b are positioned in a direction perpendicular to the optical fiber to be connected. The tips of the electrode rods 1a, 1b are formed into an approximately conical shape.

Electrode rods 1a and 1b are each supported by a bearing 5. The bearing 5 has a roughly circular outer shape and is positioned in a V-groove 13. Note that, in the present invention, even when the bearing 5 to which electrode rods 1a and 1b are fixed is positioned in the V-groove 13, this is simply considered to mean that electrode rods 1a and 1b are positioned in the V-groove 13.

The bearing 5 has concentrically arranged inner and outer rings 5a and 5b, and rolling elements (balls or rollers) arranged between the inner and outer rings 5a and 5b. The electrode rods 1a and 1b are joined to the inner ring 5a. The rolling elements allow the inner and outer rings 5a and 5b to rotate relative to each other, and therefore the electrode rods 1a and 1b can rotate relative to the outer ring 5b.

In this case, to prevent axial wobble of the electrode rods 1a and 1b when they rotate, it is preferable that the inner ring portion 5a support the electrode rods 1a and 1b for a long length. For this reason, if the rolling elements are balls, it is desirable to arrange the rolling elements in multiple rows (two rows in the illustration), or to use needle-type rollers of a certain length. It is also possible to use multiple bearings 5, with each of the electrode rods 1a and 1b being held by multiple bearings 5.

A fixed lid 7 is placed above the bearing 5 and is fixed by a fixing member (not shown). That is, the outer ring portion 5b of the bearing 5 is sandwiched and fixed between the fixed lid 7 and the V-groove 13. By fixing the bearing 5 to the V-groove 13 of the holding member 3 using the fixed lid 7, the electrode rods 1a and 1b (bearings 5) can be positioned horizontally and vertically (in the figure, in the directions perpendicular to the paper surface and up and down).

An electrode (not shown) formed on the fixed lid 7 contacts the bearing 5 and is electrically connected to the electrode rods 1a and 1b via the bearing 5. In other words, the fixed lid 7 serves as a power supply section that supplies power to the electrode rods 1a and 1b via the bearing 5.

A positioning portion 17 is provided on a part of the outer ring portion 5b of the bearing 5. The positioning portion 17 is, for example, joined to one surface of the outer ring portion 5b and is positioned so as to protrude radially. For example, as shown in the figure, the positioning portion 17 is positioned facing downward (the side opposite the fixed lid 7).

The electrode rods 1a, 1b (bearings 5) can be positioned in the axial direction by abutting the positioning portion 17 formed on part of the bearing 5 against the end face of the holding member 3. In other words, by fixing the bearing 5 with the fixing cover 7 in this state, the electrode rods 1a, 1b (bearings 5) can be positioned in each direction (axial, horizontal, and vertical).

A bevel gear 9a is disposed near the rear ends of the electrode rods 1a and 1b. The bevel gear 9a is fixed to the electrode rods 1a and 1b, and the rotational force from the bevel gear 9a is transmitted to the electrode rods 1a and 1b. The bevel gear 9a may also contact the side of the inner ring portion 5a, transmitting the rotational force from the bevel gear 9a to the inner ring portion 5a by friction or the like. In other words, the bevel gear 9a can rotate together with the electrode rods 1a and 1b (inner ring portion 5a). A motor 11 is disposed below the rear ends of the electrode rods 1a and 1b near the rear ends. The motor 11 is disposed with its rotational shaft facing upward, and the bevel gear 9b is fixed to the rotational shaft.

Because the bevel gears 9a and 9b mesh with each other, the pair of electrode rods 1a and 1b are arranged to be rotatable via the bevel gears 9a and 9b by the motor 11. In other words, the motor 11 functions as a rotation drive unit for the electrode rods 1a and 1b, and the motor 11 can rotate the electrode rods 1a and 1b around the rotation axis roughly in the axial direction of the electrode rods 1a and 1b.

The rear end surfaces of the electrode rods 1a and 1b are insulated. The holding member 3 and the bevel gears 9a and 9b (or at least one of the bevel gears 9a and 9b) are made of an insulating material such as ceramic. This prevents electricity supplied from the fixed cover 7 from flowing to any parts other than the electrode rods 1a and 1b.

Here, the motor 11 is positioned below the electrode rods 1a and 1b, with its rotational axis facing upward. Therefore, the rotational axis of the motor 11 is approximately perpendicular to the rotational axes of the electrode rods 1a and 1b, and the motor 11 is not directly connected to the electrode rods 1a and 1b. Therefore, the motor 11 and bevel gear 9b do not get in the way when attaching or detaching the electrode rods 1a and 1b. Therefore, by removing the fixed cover 7, the electrode rods 1a and 1b and bearing 5 can be easily attached or detached from the holding member 3.

Next, we will explain the operation of the fusion splicer and the method for fusing optical fibers together using the fusion splicer. As mentioned above, the tips of the optical fibers held in the holder are butted together and placed between the electrode rods 1a and 1b. In this state, an arc is generated between the pair of electrode rods 1a and 1b, melting the tips of the optical fibers and splicing them together.

Here, a control unit (not shown) drives the motor 11 to rotate the electrodes 1a and 1b before applying voltage to the electrodes 1a and 1b. In this state, power can be supplied to the electrodes 1a and 1b to cause a discharge between them. In other words, the motor 11 can rotate the electrodes 1a and 1b while they are discharging. Therefore, with the optical fibers positioned opposite each other on the holding member 3, the electrodes 1a and 1b can be rotated to discharge the optical fibers, thereby fusing them together.

The rotation directions of the pair of electrode rods 1a and 1b can be the same. Figure 2(a) is a diagram showing the rotation direction of electrode rods 1a and 1b as viewed from arrow A in Figure 1(a). Note that D in Figure 2(a) is the horizontal direction (the direction perpendicular to the paper surface of Figure 1(a)), and E is the vertical direction (the up and down direction in Figure 1(a)).

Here, "the same direction of rotation" means that they rotate in the same direction when viewed from one side of the rotation axis (for example, direction A in Figure 1(a)). For example, in Figure 1(a), when electrode rods 1a and 1b rotate in the same direction, it means that they each rotate in the direction of arrow B in the figure. In other words, the direction of rotation of electrode rod 1a when viewed from the tip of electrode rod 1a (direction B is counterclockwise) is opposite to the direction of rotation of electrode rod 1b when viewed from the tip of electrode rod 1b (direction B is clockwise).

As shown in Figure 2(a), the rotation angle of electrode rods 1a and 1b when they both rotate in direction B is θ. Figure 2(b) is a diagram showing the relationship between rotation angle θ and time t, and Figure 2(c) is a diagram showing the relationship between sin θ and time t for rotation angle θ. In this way, θ increases in proportion to time t. In other words, in this embodiment, the rotation speed of electrode rods 1a and 1b is constant.

The discharge time required for fusion splicing varies depending on the optical fiber. For example, a single optical fiber can be spliced with about one second of discharge, but an optical fiber ribbon can take several tens of seconds. In this case, the rotation speed is set so that at least 10 rotations are possible during discharge. For example, the rotation speed is set so that 10 or more rotations are possible per second.

By discharging while rotating in this way, even if the discharge originates at a location other than the tip of the electrode rods 1a and 1b and the center of the discharge part is formed at a position offset from the center of the optical fiber, the position of the discharge part can be moved circumferentially over time. This makes the position of the discharge part generally uniform, preventing excessive or insufficient melting of parts of the optical fiber, and allowing the optical fiber to be melted and fused approximately uniformly.

The rotation directions of the pair of electrode rods 1a, 1b may be opposite. Figure 3(a) is a diagram showing the relationship between the rotation angle θ of each of electrode rods 1a, 1b and time t, and Figure 3(b) is a diagram showing the relationship between sin θ and time t for the rotation angle θ of each of electrode rods 1a, 1b. For example, solid line F in the diagram represents electrode rod 1a, and wire G in the diagram represents electrode rod 1b. That is, for example, electrode rod 1a rotates in direction B in Figure 1(a), and electrode rod 1a rotates in direction C in Figure 1(a). Thus, in this embodiment, electrode rods 1a, 1b rotate in opposite directions at approximately the same rotational speed.

Even in this way, the position of the discharge part can be moved circumferentially over time, making the discharge part approximately uniform throughout the entire discharge period, preventing excessive melting in some areas or insufficient melting in others, and allowing the optical fiber to be melted and fused approximately uniformly.

The pair of electrode rods 1a, 1b may also rotate at different speeds. Figure 4(a) is a diagram showing the relationship between the rotation angle θ of each of the electrode rods 1a, 1b and time t, and Figure 4(b) is a diagram showing the relationship between sin θ and time t for the rotation angle θ of each of the electrode rods 1a, 1b. For example, the solid line H in the diagram represents electrode rod 1a, and the electric wire I in the diagram represents electrode rod 1b. In this embodiment, electrode rods 1a, 1b rotate in the same direction but at different rotation speeds.

In this way, by changing the rotation speed, the relative positional relationship between the electrode rods 1a and 1b can be varied over time, which makes the discharge area approximately uniform during the discharge period, preventing excessive or insufficient melting in some areas, and allowing the optical fiber to be melted and fused approximately uniformly. It is also possible to change the rotation speed by reversing the rotation direction of the electrode rods 1a and 1b.

As described above, according to the first embodiment, by rotating the electrode rods 1a and 1b around their respective axial directions as the rotation axis during discharge, even if the discharge starting point is shifted from the center of the electrode rods 1a and 1b (center of the rotation axis), the discharge part will not be biased in a fixed direction. In this way, by intentionally varying the position of the discharge part over time, it is possible to achieve a substantially uniform discharge overall, thereby melting the optical fiber substantially uniformly and achieving high-quality fusion splicing. This makes it possible to reduce the frequency of cleaning and replacing the electrode rods 1a and 1b with new ones.

In addition, the rotation of the electrode rods 1a and 1b by the motor 11 is performed via bevel gears 9a and 9b that are approximately perpendicular to each other, making it easy to attach and detach the electrode rods 1a and 1b.

In addition, by providing a positioning portion 17 on the bearing 5, it is possible to position the electrode rods 1a and 1b in the axial direction.

In addition, by insulating the areas near the rear ends of the electrode rods 1a and 1b and constructing certain components from insulating materials, it is possible to prevent discharge from the rear of the electrode rods 1a and 1b to other components.

Second Embodiment
Next, a second embodiment will be described. Fig. 5(a) is a cross-sectional view of the vicinity of the electrodes 1a and 1b according to the second embodiment. In the following description, components having the same functions as those in the first embodiment will be assigned the same reference numerals as those in Fig. 1(a) and the like, and redundant description will be omitted.

In the second embodiment, multiple V-grooves 15 are formed in the holding member 3 and arranged in parallel. In the first embodiment, the optical fibers to be connected may be single-core optical fibers or optical fiber ribbons in which multiple single-core optical fibers are arranged in parallel, but this embodiment is primarily intended for connecting optical fiber ribbons.

In the second embodiment, portions of electrode rods 1a and 1b are bent (or curved). That is, the tip positions of electrode rods 1a and 1b are positioned offset from the rotation axis. Here, the rotation axis of electrode rods 1a and 1b coincides with the rotation axis of bearing 5. Even in this case, the rotation axis of electrode rod 1a and the rotation axis of electrode rod 1b substantially coincide, and electrode rods 1a and 1b are positioned substantially on the same axis.

As shown in Figure 5(b), a stepped eccentric portion may be formed on part of electrode rods 1a and 1b. This also allows the tip positions of electrode rods 1a and 1b to be positioned offset from the rotation axis. In either case, the amount of offset of the tip positions of electrode rods 1a and 1b from the rotation axis is approximately the same.

The tip positions of the respective electrodes 1a and 1b are positioned at positions that are approximately 180° out of phase with each other in the direction of rotation. Figure 6(a) is a diagram corresponding to Figure 2(a) and shows the tip positions of the respective electrodes 1a and 1b. For example, if the solid line J in the figure represents electrode 1a and the electric wire K in the figure represents electrode 1b, the tip position of electrode 1a at t=0 is L in the figure, and the tip position of electrode 1b at t=0 is M in the figure.

Figure 6(b) corresponds to Figure 2(b) and shows the relationship between the rotation angle θ and time t, while Figure 6(c) corresponds to Figure 2(c) and shows the relationship between sin θ and time t with respect to the rotation angle θ. In this embodiment, θ also increases in proportion to time t, and the electrode rods 1a and 1b rotate at approximately the same speed and in the same direction.

In this way, when the tip positions of electrode rods 1a and 1b are rotated in the same direction and at the same speed with a phase shift of approximately 180°, the line connecting the tip positions of electrode rods 1a and 1b always passes through the axis of rotation approximately in the middle between electrode rods 1a and 1b. In other words, the relative positional relationship (180° phase shift) between the tip positions of electrode rods 1a and 1b with respect to the axis of rotation remains unchanged, but the tip positions rotate around the axis of rotation.

The amount of deviation in the tip positions of the electrode rods 1a and 1b should be such that they do not interfere with other components (e.g., the holding member 3) during rotation. For example, it is desirable that the deviation be such that a portion of the electrode rods 1a and 1b does not extend beyond the outer periphery of the bearing 5 when viewed from the direction of the rotation axis.

Figure 7(a) is a conceptual diagram showing the discharge state when fusing a typical optical fiber ribbon 19. Typically, the tip positions (discharge starting points) of the electrode rods 1a and 1b are arranged on the same axis, and the optical fiber ribbon 19 is placed between the tips. In this case, the dotted lines in the diagram are conceptual diagrams of the isothermal lines of the discharge area. In this case, it is desirable that all of the optical fibers that make up the optical fiber ribbon be arranged in as similar a temperature distribution area as possible.

However, under normal conditions, it is difficult to achieve a uniform temperature distribution between the optical fibers closest to the electrode rods 1a and 1b (the optical fibers at both ends of the optical fiber ribbon 19) and the optical fibers further away (the optical fibers near the center of the optical fiber ribbon 19). For this reason, it is necessary to set the relative positions of the electrode rods 1a and 1b and the appropriate relative positioning of the optical fiber ribbon 19 with respect to the electrode rods 1a and 1b.

In contrast, Figure 7(b) shows a state in which the tip positions of electrode rods 1a and 1b are arranged on different axes and are offset from each other on opposite sides of the optical fiber ribbon 19. By arranging electrode rods 1a and 1b offset above and below the optical fiber ribbon 19 in this way, the shape of the isothermal region changes, making it possible to reduce the temperature distribution for each optical fiber in the optical fiber ribbon 19.

However, with this method, there is a risk of temperature distribution occurring between the top and bottom of the optical fibers at both ends of the optical fiber ribbon 19. Therefore, as shown in Figure 7(c), by reversing the arrangement of the electrode rods 1a and 1b relative to the optical fiber ribbon 19 from the state shown in Figure 7(b), a more uniform temperature distribution can be achieved overall.

In this embodiment, the electrode rods 1a and 1b, whose tip positions are offset from each other, are rotated, so that the tip positions of the electrode rods 1a and 1b move by alternately repeating the states shown in Figures 7(b) and 7(c). As a result, the optical fiber ribbon 19 can be fused with a more uniform temperature distribution overall.

The second embodiment can achieve the same effects as the first embodiment. Furthermore, when fusion splicing the optical fiber ribbon 19, each optical fiber can be fused more uniformly.

In the second embodiment, the electrode rods 1a and 1b may be rotated in different directions, so that the relative positional relationship (phase shift) between the tip positions of the electrode rods 1a and 1b changes over time. In this case, the optical fiber ribbon 19 can be fused with a more uniform temperature distribution than when the relative positional relationship (phase shift) between the tip positions of the electrode rods 1a and 1b does not change over time. Similarly, the rotation speeds of the electrode rods 1a and 1b may be different from each other so that the relative positional relationship (phase shift) between the tip positions of the electrode rods 1a and 1b changes over time. By periodically or randomly varying the shape of the discharge area during fusion, the discharge area can be made uniform overall. In the second embodiment, the tip positions of the electrode rods 1a and 1b may not be the discharge starting point. However, even in this case, the position of the discharge starting point can be changed by varying the tip positions, achieving the same effect. It goes without saying that the second embodiment can also be used to fusion-splice single-core optical fiber core wires.

Although the embodiments of the present invention have been described above with reference to the attached drawings, the technical scope of the present invention is not limited to the above-described embodiments. It is clear that a person skilled in the art could conceive of various modifications or alterations within the scope of the technical ideas set forth in the claims of the utility model, and it is understood that these also naturally fall within the technical scope of the present invention.

For example, the arrangement of the motor 11 and the power transmission mechanism are not limited to the example shown in the figure. Other gear structures, etc., may be used as long as the rotational force of the rotation drive unit can be transmitted to the electrode rods 1a and 1b. Furthermore, instead of providing a rotation drive unit for each of the electrode rods 1a and 1b, a single rotation drive unit (e.g., a motor) may rotate both electrode rods 1a and 1b.

In addition, in the above example, both of the pair of electrode rods 1a, 1b are rotatable by their respective rotation drive units, but it is also possible to rotate at least one of the electrode rods 1a, 1b. For example, as long as at least one of the electrode rods can be rotated, it is not necessary to rotate all of the electrode rods. In addition, in the above embodiment, an example is shown in which a pair of electrode rods 1a, 1b is used, but this is also applicable to cases in which three electrode rods are used. In this case, too, it is possible to rotate at least some of the electrode rods, or all of the electrode rods.

1a, 1b... Electrode rod 3... Holding member 5... Bearing 5a... Inner ring portion 5b... Outer ring portion 7... Fixed lids 9a, 9b... Bevel gears 11... Motors 13, 15... V-groove 17... Positioning portion 19... Optical fiber ribbon 100... Fusion splicer 101... Electrode rod 103... Holding member 105... Holder mounting portion 107... Fixed lid 109... Optical fiber 111... Discharge portion

Claims (10)

A fusion splicer that connects optical fibers arranged opposite to each other,
At least one pair of electrode rods arranged in a direction perpendicular to the optical fiber;
a rotation drive unit that can rotate at least one of the electrode rods around a rotation axis substantially in the axial direction of the electrode rod,
A fusion splicer characterized in that, with the optical fibers arranged opposite each other on a holding member, the electrode rod is rotated multiple times while discharging, thereby fusing the optical fibers together. The fusion machine according to claim 1, characterized in that the pair of electrode rods are each rotatable by the rotary drive unit, and the pair of electrode rods rotate in the same direction. A fusion splicer as described in claim 1, characterized in that the tips of the pair of electrode rods are located on the rotation axis of the electrode rods. A fusion splicer according to claim 2 or 3, characterized in that the pair of electrode rods rotate at different speeds. A fusion splicer according to any one of claims 1 to 4, characterized in that the pair of electrode rods can each be rotated by the rotation drive unit, the rotation axes of the pair of electrode rods are approximately aligned, the pair of electrode rods rotate at approximately the same rotation speed, the tip positions of the electrode rods are positioned 180° out of phase with each other in the direction of rotation, and the pair of electrode rods rotate while maintaining the relative positional relationship of the tips of the pair of electrode rods. A V-shaped groove is formed in the holding member that holds the electrode rod.
a bearing is disposed in the V-groove, and the electrode rod is supported by the bearing;
6. The fusion splicer according to claim 1, wherein the electrode rod can be positioned by fixing the bearing to the holding member with a fixing cover while a positioning portion formed on a part of the bearing is brought into contact with an end face of the holding member. A fusion splicer according to any one of claims 1 to 6, characterized in that the optical fiber is an optical fiber ribbon in which multiple single-core optical fibers are arranged in parallel. A method for fusing optical fibers using the fusion splicer according to any one of claims 1 to 7, comprising:
A method for splicing optical fibers, characterized in that the optical fibers are arranged opposite each other on a holding member, and the electrode rod is rotated multiple times while discharging, thereby fusing the optical fibers together. The optical fiber fusion method according to claim 8, characterized in that the optical fiber is an optical fiber ribbon in which multiple single-core optical fibers are arranged in parallel. The optical fiber fusion method according to claim 8, characterized in that after the electrode rods are rotated, discharge is initiated between the electrode rods in that state.