JP7129441B2 - fusion splicer - Google Patents

Description

The present invention relates to a fusion splicer for fusion splicing optical fibers.

A fusion splicer is used to connect optical fibers. The fusion splicer connects optical fibers held by a pair of holders to each other by arranging them between electrodes and by fusing the ends of the optical fibers with an arc.

A high-voltage power supply is used in such a fusion splicer in order to generate an arc and stably maintain the arc (for example, Patent Document 1).

JP-A-2006-208740

FIG. 4A is a cross-sectional view showing an installation state when the optical fiber 115 is fused. As shown, optical fiber 115 is positioned between a pair of electrodes 109 . The electrode 109 is fixed to the fusion splicer by means of an electrode holding member 111, a screw 113 for fixing the same, and the like. By generating an arc between the pair of electrodes 109 in this state, the tip of the optical fiber 115 can be melted and joined.

Here, the pair of electrodes 109 are arranged with an interval (G in the drawing). Therefore, when fusion bonding is performed, it is necessary to break the insulation in this gap (air layer) to cause electric discharge and generate an arc.

FIG. 5 is a conceptual diagram showing the voltage fluctuation of the electrode 109 at this time, where the horizontal axis indicates time t and the vertical axis indicates potential V. As shown in FIG. D (solid line) in the drawing indicates the potential of one electrode 109 , and E (broken line) in the drawing indicates the potential of the other electrode 109 .

As shown in Patent Document 1, in order to first start a discharge (arc generation) between the electrodes 109, a high voltage enough to cause dielectric breakdown is required. Therefore, at the initial stage of fusion bonding (range X in the figure), dielectric breakdown (arc generation) can be caused by raising one electrode 109 to a predetermined potential (F in the figure).

On the other hand, once dielectric breakdown occurs, plasma is generated between the electrodes. Therefore, after dielectric breakdown (range Y in the figure), the arc can be stably maintained even at a lower voltage. Usually, at this time, a high-frequency AC voltage is applied between the electrodes.

Note that in a general power supply circuit, the other electrode 109 is grounded and has a potential of 0 in order to reduce the size of the circuit.

However, in recent years, the use of an optical fiber ribbon in which a plurality of optical fibers are arranged side by side and integrated is increasing. In order to connect such optical fiber tape core wires, it is desirable to fuse them collectively rather than fuse each optical fiber individually.

FIG. 4B is a conceptual diagram showing a state in which a plurality of optical fibers 115 are fused. In this case, multiple optical fibers 115 are arranged between the pair of electrodes 109 . In this way, when connecting optical fiber tape core wires in which a plurality of optical fibers are arranged side by side, the distance between the electrodes 109 (H in the figure) is set as compared to the case of connecting single optical fibers. need to be wider.

However, since the voltage required for dielectric breakdown is proportional to the distance between the electrodes 109, the wider the distance between the electrodes 109, the higher the potential (F in FIG. 5) required to first cause dielectric breakdown (arcing). . When the potential of the electrode 109 increases, there is a risk of dielectric breakdown occurring at a portion where insulation has been maintained up to now. For example, since the potential of the electrode holding member 111 and screw 113 for fixing the electrode 109 also increases, there is a risk of dielectric breakdown occurring between other parts (grounded parts) in the fusion splicer.

In order to prevent this, it is necessary to ensure that insulation breakdown does not occur at unintended locations, such as by providing intervals between individual components. However, designing each part in this manner increases the size of the device itself. Therefore, a fusion splicer that is more compact and can stably perform fusion is desired.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a fusion splicer capable of stably performing fusion splicing even when the distance between electrodes is widened.

In order to achieve the above object, the present invention provides a fusion splicer for splicing optical fibers, comprising a pair of electrodes arranged in a fusion splicing portion for butting and splicing the tips of the optical fibers; a pair of voltage circuits connected to the electrodes and applying voltage to the electrodes; and a control section for controlling the voltage of each of the voltage circuits . The control unit is capable of applying positive and negative voltages to each of the electrodes so that the potentials of the electrodes are opposite to each other until discharge is started between the electrodes at the time of fusion bonding. A fusion splicer characterized by:

The control section may apply high-frequency voltages to the respective electrodes so that the potentials of the respective electrodes are in opposite phases after the discharge is started between the electrodes.

After the discharge is started between the electrodes, the controller may ground one of the electrodes and apply a high-frequency voltage to the other electrode.

According to the present invention, although it is necessary to use two booster circuits for causing dielectric breakdown, by boosting the respective voltages with opposite potentials, the voltage of the sum of the positive and negative potentials of the individual electrodes is generated between the electrodes. can be applied. Therefore, even if the distance between the electrodes is widened, dielectric breakdown can occur between the electrodes.

Moreover, even if the potential difference between the electrodes is increased, the absolute values of the positive and negative potentials of the individual electrodes do not need to be increased. Therefore, it is possible to suppress the occurrence of dielectric breakdown with other parts (grounded parts).

In addition, after the start of discharge, the arc can be stably maintained by reversing the phases of the respective electrodes to provide a high-frequency AC voltage.

Also, by grounding one of the electrodes after the start of discharge, voltage control is facilitated.

According to the present invention, it is possible to provide a fusion splicer capable of stably performing fusion even if the distance between electrodes is widened.

FIG. 2 is a perspective view showing the fusion splicer 100; A diagram showing the voltage control system 10 (a), (b) is a conceptual diagram which shows the electric potential change of each electrode. 4A and 4B are diagrams showing a state in which an optical fiber 115 is arranged between electrodes 109; FIG. FIG. 2 is a conceptual diagram showing potential changes of conventional electrodes.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a fusion splicer 100. As shown in FIG. The fusion splicer 100 is capable of operating a fusion splicing unit 101 that fuses optical fibers, a heating unit 103 that heats spliced portions of optical fibers, and the fusion unit 101 and the heating unit 103 . It has an operation unit 105 and the like.

An openable and closable windshield is arranged in the fused part 101, and a pair of holder placing parts 107 are arranged inside to face each other. The holder mounting portion 107 is a portion on which a holder holding an optical fiber is mounted. A base portion is arranged between the holder placing portions 107, and a pair of electrodes 109 are arranged on the base portion. That is, in a fusion splicer 100 for splicing optical fibers, a pair of electrodes 109 are arranged in a fusion splicing portion 101 where the tip portions of the optical fibers are butted and spliced.

When splicing optical fibers using the fusion splicer 100 , first, the windshield of the fusion splicer 101 is opened, and a pair of holders holding the optical fibers in advance is set on the holder mounting section 107 inside. As a result, as shown in FIG. 4, the ends of the optical fibers protruding from the ends of the holders are brought into contact with each other between the pair of electrodes 109 . By applying a predetermined voltage between the electrodes 109 in this state, discharge is started.

FIG. 2 is a diagram showing the configuration of the voltage control system 10 for controlling the voltage of the pair of electrodes 1a and 1b in the fusion splicer 100. As shown in FIG. The voltage control system 10 mainly includes a control section 5, voltage circuits 3a and 3b, and the like.

Electrode 1a is connected to voltage circuit 3a, and electrode 1b is connected to voltage circuit 3b. That is, a pair of electrodes 1a, 1b are connected to a pair of voltage circuits 3a, 3b, respectively. A voltage can be applied to the electrodes 1a, 1b by respective voltage circuits 3a, 3b.

The voltage circuit 3a has a discharge starting voltage circuit 7a and a high frequency voltage circuit 9a. Also, the voltage circuit 3b has a discharge start voltage circuit 7b and a high frequency voltage circuit 9b. The discharge start voltage circuits 7a and 7b (including boosting transformers and the like) are, as described above, circuits that generate a voltage until the first start of discharge. Further, the high-frequency voltage circuits 9a and 9b are circuits for generating a voltage for maintaining the arc after the discharge is started.

Each voltage circuit 3a, 3b is connected to a control unit 5 such as a CPU. Note that the controller 5 may be arranged for each of the voltage circuits 3a and 3b. The control unit 5 can control voltages generated by the voltage circuits 3a and 3b. That is, the control unit 5 can control the operation of the voltage circuits 3a and 3b, switch between the discharge start voltage circuits 7a and 7b and the high frequency voltage circuits 9a and 9b, and apply a desired voltage between the electrodes.

Next, details of voltage control of the electrodes 1a and 1b by the controller 5 will be described. FIG. 3(a) is a diagram showing potential changes of the electrodes 1a and 1b, where the horizontal axis is time t and the vertical axis is potential V. FIG. As described above, the voltage control differs between the range X before the first discharge is started and the range Y in which the discharge is stably maintained after the discharge is started.

In this embodiment, the control unit 5 controls the electrodes 1a and 1b so that the potentials of the electrodes 1a and 1b are opposite to each other until the discharge between the electrodes 1a and 1b is started at the time of fusion bonding. It is possible to apply positive and negative voltages to , respectively. In other words, the controller 5 can independently control the voltages of the electrodes 1a and 1b before the discharge starts. More specifically, the control unit 5 uses the discharge start voltage circuit 7a of the voltage circuit 3a and the discharge start voltage circuit 7b of the voltage circuit 3b to determine the potential of one electrode 1a (A in the figure) and the potential of the other electrode 1a. The potential of the electrode 1b (B in the drawing) is controlled so as to be opposite to each other in the region before the start of discharge.

In the illustrated example, a voltage of -C (V) is applied to the electrode 1a and a voltage of +C (V) is applied to the electrode 1b. Therefore, a voltage of 2C (V) is applied between the electrodes 1a and 1b. In this embodiment, a discharge voltage of 2C (V) initiates a discharge between the electrodes 1a and 1b. The potentials of the electrodes 1a and 1b before the start of discharge are preferably controlled so that their absolute values are substantially the same and only the positive and negative are reversed.

After the discharge is started, the discharged state can be maintained by a voltage sufficiently lower than the discharge voltage. Therefore, after the discharge is started between the electrodes 1a and 1b, the controller 5 switches from the discharge start voltage circuits 7a and 7b to the high frequency voltage circuits 9a and 9b. That is, the control unit 5 uses the high-frequency voltage circuit 9a of the voltage circuit 3a and the high-frequency voltage circuit 9b of the voltage circuit 3b so that the potentials of the electrodes 1a and 1b are in opposite phases. , 1b can be applied with a high-frequency alternating voltage.

As shown in FIG. 3(b), after the discharge is started between the electrodes 1a and 1b, the controller 5 grounds one electrode 1b and controls only the potential of the other electrode 1a by high frequency. , a high frequency voltage may be applied between the electrodes. That is, the control unit 5 may perform voltage control using only the high-frequency voltage circuit 9a of the voltage circuit 3a.

Switching from the discharge starting voltage circuits 7a and 7b to the high frequency voltage circuits 9a and 9b by the control unit 5 may be performed after it is detected that a current has flowed due to dielectric breakdown. The switching may be performed after checking the discharge with a camera or the like. That is, control of the potentials of the electrodes 1a and 1b by the control unit 5 may be the same as the conventional control, except that the potentials of the electrodes 1a and 1b are controlled to positive and negative potentials before the start of discharge.

As described above, according to the present embodiment, since the potentials of the electrodes 1a and 1b at the start of discharge are controlled to be opposite to each other, the potentials of the electrodes 1a and 1b are suppressed while the discharge between the electrodes 1a and 1b is suppressed. The starting potential can be higher.

In a general fusion splicer, only one circuit (such as a step-up transformer) is used to start discharge. This is a factor in increasing the size of the device and complicating the structure. In addition, since there are two high-voltage circuits, it may be necessary to take measures to prevent overheating, and there may be problems such as a decrease in the number of times the device is used when it is driven by a battery, for example.

However, since the potential of each electrode can be lowered, it is possible to suppress the occurrence of dielectric breakdown or the like at an unintended site. For example, as described above, when the electrode potential is increased, before dielectric breakdown occurs between the electrodes, the electrode holding member, screw, etc. for fixing the electrodes and other adjacent parts (grounding part) Insulation breakdown may occur between them. In order to prevent such unintended dielectric breakdown, it is necessary to design such as widening the intervals between the respective parts.

However, according to the present embodiment, the potential of each electrode itself can be made the same as in the conventional case, so that it is not necessary to take insulation measures such as increasing the intervals between components in each part or the intervals between circuits. As a result, a compact fusion splicer can be obtained.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the technical scope of the present invention is not influenced by the above-described embodiments. It is obvious that a person skilled in the art can conceive of various modifications or modifications within the scope of the technical idea described in the claims of the utility model registration. It is understood that it belongs to the scope.

1a, 1b... Electrodes 3a, 3b... Voltage circuit 5... Control units 7a, 7b... Discharge starting voltage circuits 9a, 9b... High frequency voltage circuit 10... Voltage control system 100... Fusion splicer 101 Fusion splicer 103 Heating unit 105 Operation unit 107 Holder mounting unit 109 Electrode 111 Electrode holding member 113 Screw 115 ……optical fiber

Claims (3)

A fusion splicer for connecting optical fibers,
a pair of electrodes arranged at a fusion portion where the tip portions of the optical fibers are butted and fused;
a pair of voltage circuits connected to each of said electrodes for applying a voltage to said electrodes;
a control unit for controlling the voltage of each of the voltage circuits;
and
other components in the fusion machine are grounded;
The control unit can apply positive and negative voltages to each of the electrodes so that the potentials of the electrodes are opposite to each other until the discharge starts between the electrodes during fusion bonding. A fusion splicer characterized by: The control unit is capable of applying a high-frequency voltage to each of the electrodes so that the potentials of the electrodes are in opposite phases after the discharge is started between the electrodes. The fuser of claim 1. 2. The fusion according to claim 1, wherein said controller grounds one of said electrodes and applies a high-frequency voltage to said other electrode after the discharge is started between said electrodes. landing.

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