JP2006208740A - High voltage power supply for machine of fusion connection of optical fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To stabilize the connection loss of an optical fiber by stabilizing a discharge wave form. <P>SOLUTION: A high voltage power supply (1) for the machine of fusion connection of the optical fiber is provided with a boosting transformer (10), a multi-stage voltage circuit (20) and a high frequency capacitor (30). As a boosting transformer (10), a straight-line layout type transformer is used in which the center axis of a primary coil (11) and the center axis of a secondary coil (12) are arranged on one and the same straight line. The center axis of the straight-line layout type transformer (10) and a substrate flat face (circuit pattern face) of a substrate (25), on which the multi-stage voltage circuit (20) and the high frequency capacitor (30) are mounted, are parallel to each other. Further, the substrate (25), on which the multi-stage voltage circuit (20) and the high frequency capacitor (30) are mounted, is imbedded in an electrically insulating resin (60) and the straight-line layout type transformer (10) is not imbedded in the electrically insulating resin (60). <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a high voltage power supply device used for an optical fiber fusion splicer.

  In general, there is a high voltage power supply device used for an optical fiber fusion splicer including a step-up transformer, a multistage voltage doubler circuit, and a high frequency capacitor (see, for example, Patent Document 1). An example of the high-voltage power supply device for the optical fiber fusion splicer is shown in FIG.

As shown in FIG. 8, in the conventional high voltage power supply device 101 for an optical fiber fusion splicer, a high frequency AC voltage obtained by the control circuit 115 switching the semiconductor switching element 116 is applied to the primary winding 111. The step-up transformer 110, the multi-stage voltage doubler circuit 120 for rectifying the high-frequency AC voltage of the secondary winding 112 of the step-up transformer 110 to the discharge start voltage at which the discharge electrode bar 140 starts discharging, and the discharge electrode bar 140 After the start of the discharge, a high-frequency capacitor 130 for applying a high-frequency AC voltage of a predetermined level lower than the discharge start voltage to the high-voltage side electrode of the discharge electrode bar 140 is provided instead of the multistage voltage doubler circuit 120.
JP 2001-245473 A

  However, the conventional high-voltage power supply device 101 for an optical fiber fusion splicer as described above has the following problems.

  That is, in the step-up transformer 110 used in the conventional high-voltage power supply device 101 for the optical fiber fusion splicer, the central axis C111 of the primary winding 111 and the central axis C112 of the secondary winding 112 are arranged in parallel. They are not arranged on the same straight line.

  Therefore, such a step-up transformer 110 has poor conversion efficiency of the transformer from the primary winding 111 to the secondary winding 112, and the secondary winding obtained by boosting the AC voltage on the primary winding 111 side. The AC voltage waveform on the 112 side is distorted, and spike noise occurs.

  Then, noise generated in the AC voltage waveform on the secondary winding 112 side of the step-up transformer 110 naturally rides on the multistage voltage doubler circuit 120 and the high-frequency capacitor 130 that allows high frequency to pass. The discharge waveform due to the above becomes unstable.

  As a result, fluctuations in the amount of heat applied from the discharge electrode rod 140 to the optical fiber being connected are unavoidable, and unstable optical fiber connection loss occurs, so the connection quality of the optical fiber by the optical fiber fusion splicer is impaired. Can't improve it.

  Further, in the step-up transformer 110 used in the conventional high-voltage power supply device 101 for the optical fiber fusion splicer, spike noise is generated in the AC voltage waveform on the secondary winding 112 side, and this noise is generated by the multistage voltage doubler circuit 120. In other words, a high voltage is applied to the multistage voltage doubler circuit 120, the high frequency capacitor 130, and the step-up transformer 110.

  In general, there is no problem if the creepage distance is 1 mm per 1 kV, but the creepage distance cannot be increased because the multi-stage voltage doubler circuit 120 and the secondary winding 112 side of the step-up transformer 110 are densely packed.

  Therefore, in the case of the conventional high-voltage power supply device 101 for an optical fiber fusion splicer, a portion to which a high voltage is applied, that is, the step-up transformer 110, the multistage voltage doubler circuit 120, and the high-frequency capacitor 130 are electrically insulated resin 160. It is necessary to cover. Thereby, the part (high pressure mold part) covered with the electrical insulating resin 160 becomes large, and the apparatus cannot be reduced in size.

  The present invention has been made to solve the above-described problems, and provides a high-voltage power supply device for an optical fiber fusion splicer that can stabilize the discharge waveform and stabilize the connection loss of the optical fiber. With the goal.

  A high voltage power supply apparatus for an optical fiber fusion splicer according to claim 1 of the present invention is a high voltage power supply apparatus for an optical fiber fusion splicer comprising a step-up transformer, a multistage voltage doubler circuit, and a high frequency capacitor. The step-up transformer uses a linearly arranged transformer in which the central axis of the primary winding and the central axis of the secondary winding are arranged on the same straight line, and the central axis of the linearly arranged transformer And the circuit pattern surface of the substrate on which the multistage voltage doubler circuit and the high-frequency capacitor are mounted are arranged in parallel.

  A high voltage power supply apparatus for an optical fiber fusion splicer according to a second aspect of the present invention is the high voltage power supply apparatus for an optical fiber fusion splicer according to the first aspect, wherein the multistage voltage doubler circuit and the high frequency capacitor are mounted. The substrate thus obtained is embedded in an electrically insulating resin.

  A high voltage power supply apparatus for an optical fiber fusion splicer according to a third aspect of the present invention is the high voltage power supply apparatus for an optical fiber fusion splicer according to the first aspect, wherein the multistage voltage doubler circuit and the high frequency capacitor are mounted. The printed circuit board is embedded in an electrically insulating resin, and the linearly arranged transformer is not embedded in an electrically insulating resin.

  As described above, the present invention is a high voltage power supply device for an optical fiber fusion splicer including a step-up transformer, a multistage voltage doubler circuit, and a high-frequency capacitor, and the primary transformer is used as the step-up transformer. A linearly arranged transformer in which the central axis of the secondary winding and the central axis of the secondary winding are arranged on the same straight line, and the central axis of the linearly arranged transformer, the multistage voltage doubler circuit, and the high-frequency capacitor are mounted Since the circuit pattern surface of the printed circuit board is arranged in parallel, it is possible to improve the conversion efficiency of the step-up transformer, obtain a stable discharge, and stabilize the connection loss of the optical fiber. There is an effect that can.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic block diagram showing an embodiment of a high voltage power supply device for an optical fiber fusion splicer according to the present invention. The high voltage power supply device 1 for an optical fiber fusion splicer is used as a step-up transformer. The linearly arranged transformer 10, the multistage voltage doubler circuit 20, and the high frequency capacitor 30 are provided.

  In the step-up transformer 10 used by the high-voltage power supply device 1 for an optical fiber fusion splicer according to the present invention, the central axis C11 of the primary winding 11 and the central axis C12 of the secondary winding 12 are arranged on the same straight line. The transformer having such an arrangement structure is referred to as a linear arrangement type transformer in this specification.

  A control circuit 15 and a semiconductor switching element 16 such as a transistor or FET are connected to the primary winding 11 side of the linearly arranged transformer (step-up transformer) 10, and a cockcroft is connected to the secondary winding 12 side. A multistage voltage doubler circuit 20 such as a Walton circuit and a high frequency capacitor 30 are connected.

  The multistage voltage doubler circuit 20 has one input end (high-voltage side input end) 21 connected to one end (high-voltage side end) 13 of the secondary winding 12 of the linearly arranged transformer (step-up transformer) 10. Is connected to the other end (low voltage side end) 14 of the secondary winding 12 of the linearly arranged transformer (step-up transformer) 10.

  The output terminal 23 of the multistage voltage doubler circuit 20 is connected to one electrode (high voltage side electrode) 41 of the discharge electrode bar 40 for fusion bonding of optical fibers, and the other electrode (low voltage side ( The ground side) electrode 42 is grounded.

  The high-frequency capacitor 30 includes a high-voltage side end 13 of the secondary winding 12 of the linearly arranged transformer (step-up transformer) 10 to which the high-voltage side input terminal 21 of the multi-stage voltage doubler circuit 20 is connected, and the multi-stage voltage doubler circuit 20. A multistage voltage doubler circuit 20 is connected in parallel with the output terminal 23.

  Furthermore, the low voltage of the secondary winding 12 of the linearly arranged transformer (boosting transformer) 10 to which the low voltage side (grounding side) electrode 42 of the discharge electrode bar 40 and the low voltage side input terminal 22 of the multistage voltage doubler circuit 20 are connected. A current detection circuit 50 is connected between the side end portion 14.

  The power source can be either a DC power source (battery) or an AC power source (AC adapter).

  In the case of a DC power source (battery), the DC power supplied from the DC power source (battery) is converted into high frequency AC power by turning on / off the semiconductor switching element 16 by a pulse signal of the control circuit 15, and this high frequency AC power is converted. Electric power is applied to the primary winding 11 of the linearly arranged transformer (step-up transformer) 10.

  In the case of an AC power supply, AC power supplied from the AC power supply is rectified by a rectifier and converted into DC power (AC adapter), and then the semiconductor switching element 16 is turned on / off by a pulse signal of the control circuit 15. Is converted into high frequency AC power, and this high frequency AC power is applied to the primary winding 11 of the linearly arranged transformer (step-up transformer) 10.

  The linearly arranged transformer (boosting transformer) 10 boosts the high-frequency AC voltage applied to the primary winding 11 and starts the multistage voltage doubler circuit 20 (after the discharge of the discharge electrode rod 40 starts from the secondary winding 12). This is applied to the high frequency capacitor 30).

  The multi-stage voltage doubler circuit 20 doubles and rectifies the high-frequency AC voltage of the secondary winding 12 of the linearly arranged transformer (step-up transformer) 10 to the discharge start voltage at which the discharge electrode rod 40 starts discharging. The step-up level of the linearly arranged transformer (step-up transformer) 10 can be set sufficiently smaller than the discharge start voltage required by the discharge electrode rod 40.

  In the high frequency capacitor 30, after power is supplied to the linearly arranged transformer (boosting transformer) 10, the multistage voltage doubler circuit 20 discharges the high frequency AC voltage of the secondary winding 12 of the linearly arranged transformer (boosting transformer) 10. When the discharge electrode rod 40 starts discharging by voltage double rectification to the start voltage, the discharge start voltage is replaced with the multistage voltage doubler circuit 20 that has applied the output voltage to the high voltage side electrode 41 of the discharge electrode rod 40 until then. A lower predetermined high-frequency AC voltage is applied to the high-voltage side electrode 41 of the discharge electrode bar 40.

  The current detection circuit 50 then discharges the discharge current flowing through the discharge electrode rod 40 after the discharge electrode rod 40 starts discharging (that is, discharge for optical fiber fusion splicing by the high-voltage power supply device 1 for the optical fiber fusion splicer). Current) and send a detection signal to the control circuit of the optical fiber fusion splicer (not shown), and the optical fiber fusion splicer discharges by observing the heat generation status of the connected optical fiber. The power can be controlled.

  FIG. 2 shows a linearly arranged transformer mounted on the device substrate 5 in which the substrate plane (circuit pattern surface) of the device substrate 5 of the high-voltage power supply device 1 for optical fiber fusion splicer is set parallel to the paper surface. 1 is a plan view of a step-up transformer 10 and schematically shows a plan view of a mounting substrate 25 on which a multistage voltage doubler circuit 20 and a high-frequency capacitor 30 are mounted.

  3 changes the viewpoint of the mounting state of FIG. 2 by 90 °, sets the substrate plane (circuit pattern surface) of the device substrate 5 to be perpendicular to the paper surface, and arranges the linearly arranged transformer (step-up) mounted on the device substrate 5. 1 is a schematic side view of a mounting substrate 25 on which a multistage voltage doubler circuit 20 and a high frequency capacitor 30 are mounted.

  The linearly arranged transformer (step-up transformer) 10 used as the step-up transformer by the high-voltage power supply device 1 for the optical fiber fusion splicer 1 includes a central axis C11 of the primary winding 11 and a central axis of the secondary winding 12. Since C12 and C12 are arranged on the same straight line, for example, the conversion efficiency of the transformer from the primary winding 11 to the secondary winding 12 is better than that in which both central axes are arranged in parallel.

  Therefore, there is little distortion of the AC voltage waveform on the secondary winding 12 side obtained by boosting the AC voltage on the primary winding 11 side, and from the secondary winding 12 side of the linearly arranged transformer (boost transformer) 10. There is little noise output.

  That is, for example, when the central axis C111 of the primary winding 111 and the central axis C112 of the secondary winding 112 are arranged in parallel (parallel arrangement type) as in the conventional step-up transformer 110 shown in FIG. Since the AC voltage waveform on the secondary winding 112 side is distorted and noise is generated, the discharge waveform of the discharge electrode bar 140 is distorted as shown in FIG.

  On the other hand, in the linearly arranged transformer (boosting transformer) 10 used as the boosting transformer by the high-voltage power supply device 1 for the optical fiber fusion splicer 1, the central axis and the secondary winding 12 of the primary winding 11 are used. Since the center voltage axis is arranged on the same straight line, the AC voltage waveform on the secondary winding 12 side is hardly distorted and there is substantially no noise or little noise. As shown in FIG. 4A, the discharge waveform is almost ideal.

  In addition to this, as shown in FIG. 3, the central axis of the linearly arranged transformer (step-up transformer) 10 (that is, the central axis of the primary winding 11 and the secondary winding 12 arranged on the same straight line). Since the central axis C10 and the substrate plane (circuit pattern plane P25) of the mounting substrate 25 on which the multistage voltage doubler circuit 20 and the high frequency capacitor 30 are mounted are arranged in parallel, a linearly arranged transformer (a boosting transformer) There is very little possibility that the noise output from 10 will get on the multistage voltage doubler circuit 20 and the high frequency capacitor 30.

  That is, for example, the central axis C10 of the linearly arranged transformer (step-up transformer) 10 and the substrate plane (circuit pattern plane P25) of the mounting substrate 25 on which the multistage voltage doubler circuit 20 and the high frequency capacitor 30 are mounted are orthogonal to each other. When arranged, as shown in FIG. 5B, the direction B of the magnetic field generated in the linearly arranged transformer (step-up transformer) 10 and the direction of the circuit pattern of the multistage voltage doubler circuit 20 (circuit pattern plane P25) Will be orthogonal.

  In this case, the multi-stage voltage doubler circuit 20 has a current direction I affected by a magnetic field generated from the linearly arranged transformer (step-up transformer) 10 and the direction of the circuit pattern of the multi-stage voltage doubler circuit 20 (circuit pattern). The multi-stage voltage doubler circuit 20 is affected by the magnetic field generated by the linearly arranged transformer (step-up transformer) 10.

  As a result, noise output from the linearly arranged transformer (step-up transformer) 10 can easily get on the multistage voltage doubler circuit 20 and the high-frequency capacitor 30 and cannot be avoided.

  On the other hand, the central axis C10 of the linearly arranged transformer (step-up transformer) 10 and the substrate plane (circuit pattern plane P25) of the mounting substrate 25 on which the multistage voltage doubler circuit 20 and the high frequency capacitor 30 are mounted are arranged in parallel. Then, as shown in FIG. 5A, the direction B of the magnetic field generated in the linearly arranged transformer (step-up transformer) 10 and the direction of the circuit pattern of the multistage voltage doubler circuit 20 (circuit pattern plane P25) Become parallel.

  In this case, the multi-stage voltage doubler circuit 20 has a current direction I affected by a magnetic field generated from the linearly arranged transformer (step-up transformer) 10 and the direction of the circuit pattern of the multi-stage voltage doubler circuit 20 (circuit pattern). Therefore, the multistage voltage doubler circuit 20 is not substantially affected by the magnetic field generated by the linearly arranged transformer (step-up transformer) 10.

  Thereby, the possibility that the noise output from the linearly arranged transformer (boost transformer) 10 gets on the multistage voltage doubler circuit 20 and the high frequency capacitor 30 can be effectively reduced.

  FIG. 6 is a schematic plan view showing a buried structure of the above-described high voltage power supply device 1 for an optical fiber fusion splicer using an electrically insulating resin, and FIG. 7 is a schematic side view thereof. In the high voltage power supply device 1, only the multistage voltage doubler circuit 20 and the high frequency capacitor 30 among the linearly arranged transformer (boost transformer) 10, the multistage voltage doubler circuit 20, and the high frequency capacitor 30 are embedded in the electrical insulating resin 60. .

  In other words, the high-voltage power supply device 1 for the optical fiber fusion splicer 1 embeds the mounting substrate 25 on which the multistage voltage doubler circuit 20 and the high-frequency capacitor 30 are mounted in the electrical insulating resin 60, and linearly arranges the transformer (for boosting). The transformer 10 is exposed without being embedded in the electrical insulating resin 60.

  As described above, in the case of the high-voltage power supply device 1 for the optical fiber fusion splicer, the center axis C11 of the primary winding 11 and the center of the secondary winding 12 of the linearly arranged transformer (step-up transformer) 10 are used. Since the axis C12 is arranged on the same straight line, there is little noise output from the secondary winding 12 side.

  In particular, since there is little risk of occurrence of extremely high voltage noise such as spike noise, the linearly arranged transformer (step-up transformer) 10 has a practical problem when exposed without being embedded in the electrical insulating resin 60. Absent.

  Thus, since only the multistage voltage doubler circuit 20 and the high frequency capacitor 30 need to be covered with the electric insulating resin 60 except for the linearly arranged transformer (step-up transformer) 10, the portion covered with the electric insulating resin 60 (high voltage mold portion) As a result, the size of the apparatus can be reduced, and the cost can be reduced.

  Further, as described above, in the case of the high-voltage power supply device 1 for the optical fiber fusion splicer, the central axis C10 of the linearly arranged transformer (boost transformer) 10, the multistage voltage doubler circuit 20, and the high-frequency capacitor 30 are provided. Since the substrate plane (circuit pattern surface P25) of the mounted mounting substrate 25 is arranged in parallel, noise output from the linearly arranged transformer (step-up transformer) 10 is generated by the multistage voltage doubler circuit 20 and the high frequency capacitor. There is very little possibility to ride 30.

  Therefore, the multi-stage voltage doubler circuit 20 and the high-frequency capacitor 30 covered with the electrical insulating resin 60 also take into account the high voltage of the noise that is superposed beyond the original voltage level of the circuit, and the high voltage mold portion covered with the electrical insulating resin 60 It is not necessary to increase the thickness excessively, and it is possible to cover with an appropriate thickness of the electric insulating resin 60 that protects the circuit from the original voltage level.

  As a result, the size of the high-voltage mold portion in which the mounting substrate 25 on which the multistage voltage doubler circuit 20 and the high-frequency capacitor 30 are mounted is embedded in the electrical insulating resin 60 can be made relatively small. Can be expected to be downsized, and cost reduction can also be expected.

  Next, the operation of the high-voltage power supply device 1 for an optical fiber fusion splicer configured as described above will be described.

  First, DC power of a DC power source (battery) or AC-DC conversion power of an AC power source (AC adapter) is converted to high frequency AC power by turning on / off the semiconductor switching element 16 by a pulse signal of the control circuit 15. And applied to the primary winding 11 of the linearly arranged transformer (step-up transformer) 10.

  Then, the linearly arranged transformer (boosting transformer) 10 boosts the high-frequency AC voltage applied to the primary winding 11 and applies it from the secondary winding 12 to the multistage voltage doubler circuit 20. In response to this, the multistage voltage doubler circuit 20 successively increases the voltage at the output end 23, and the voltage at the output end 23 is applied to the high voltage side electrode 41 of the discharge electrode bar 40.

  The voltage is further increased by the multistage voltage doubler circuit 20 until a discharge that breaks the air insulation between the high-voltage side electrode 41 and the low-voltage side (ground side) electrode 42 of the discharge electrode bar 40 is performed. , 42 is switched from the multistage voltage doubler circuit 20 to the high-frequency capacitor 30, whereby the voltage applied to the high-voltage side electrode 41 of the discharge electrode bar 40 is a predetermined level of high-frequency AC voltage lower than the discharge start voltage. Migrate to

  Then, a stable discharge is continued between the high-voltage side electrode 41 and the low-voltage side (ground side) electrode 42 of the discharge electrode bar 40 by the high-frequency AC voltage of a predetermined level after this transition, and the optical fiber is used by using this stable discharge. Make a fusion splice.

  As described above, the high-voltage power supply device 1 for the optical fiber fusion splicer has a linear arrangement in which the central axis C11 of the primary winding 11 and the central axis C12 of the secondary winding 12 are arranged on the same straight line. Since the transformer (a step-up transformer) 10 is used, the conversion efficiency of the transformer is good, the distortion of the AC voltage waveform on the secondary winding 12 side is small, and there is noise output from the secondary winding 12 side. There are few.

  In addition, the central axis C10 of the linearly arranged transformer (step-up transformer) 10 and the circuit pattern surface P25 of the mounting substrate 25 on which the multistage voltage doubler circuit 20 and the high frequency capacitor 30 are mounted are arranged in parallel. Therefore, there is very little possibility that noise output from the linearly arranged transformer (step-up transformer) 10 gets on the multistage voltage doubler circuit 20 and the high frequency capacitor 30.

  Thereby, the discharge waveform between the electrodes 41 and 42 of the discharge electrode rod 40 can be stabilized, the amount of heat given from the discharge electrode rod 40 to the optical fiber being connected is stabilized, and the connection loss of the optical fiber is stabilized, The connection quality of the optical fiber by the optical fiber fusion splicer can be improved.

  In the above embodiment, the multistage voltage doubler circuit 20 and the high frequency capacitor 30 are embedded in the electrical insulating resin 60, and the linearly arranged transformer (step-up transformer) 10 is exposed without being embedded in the electrical insulating resin 60. However, the present invention is not limited to this.

  That is, not only the multi-stage voltage doubler circuit 20 and the high-frequency capacitor 30 are embedded in the electrical insulating resin 60 but also a linearly arranged transformer (a step-up transformer) as required, for example, for the purpose of ensuring extremely high safety. 10 can also be embedded in the electrically insulating resin 60.

It is a schematic block diagram which shows one Embodiment of the high voltage power supply device for optical fiber fusion splicers by this invention. It is a schematic plan view which shows the mounting direction of a linear arrangement type | mold transformer and a multistage voltage doubler circuit. It is a schematic side view which shows the mounting direction of a linear arrangement type | mold transformer and a multistage voltage doubler circuit. It is a wave form diagram which shows a different discharge waveform with a linear arrangement type | formula transformer and a parallel arrangement type | mold transformer. It is explanatory drawing which shows the influence of the magnetic field by the mounting direction of the multistage voltage doubler circuit with respect to the central axis of a linear arrangement type | mold transformer. It is a schematic plan view which shows the embedding structure by the electrically insulating resin of the high voltage power supply device for optical fiber fusion splicers. It is a schematic side view which shows the embedding structure by the electrically insulating resin of the high voltage power supply device for optical fiber fusion splicers. It is a schematic block diagram which shows an example of the conventional high voltage power supply apparatus for optical fiber fusion splicers.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 High voltage power supply device for optical fiber fusion splicers 5 Device substrate 10 Linear arrangement type transformer (transformer for boosting)
11 Primary winding 12 Secondary winding 13 High voltage side end 14 Low voltage side end 15 Control circuit 16 Semiconductor switching element 20 Multi-stage voltage doubler circuit 21 High voltage side input terminal 22 Low voltage side input terminal 23 Output terminal 25 Mounting board 30 High frequency Capacitor 40 Discharge electrode rod 41 High voltage side electrode 42 Low voltage side (ground side) electrode 50 Current detection circuit 60 Electrical insulating resin

Claims (3)

A high-voltage power supply device for an optical fiber fusion splicer comprising a step-up transformer, a multistage voltage doubler circuit, and a high-frequency capacitor,
As the step-up transformer, a linearly arranged transformer in which the central axis of the primary winding and the central axis of the secondary winding are arranged on the same straight line is used.
A high voltage power supply for an optical fiber fusion splicer, wherein the central axis of the linearly arranged transformer and a circuit pattern surface of a substrate on which the multistage voltage doubler circuit and the high frequency capacitor are mounted are arranged in parallel. apparatus.   2. The high voltage power supply device for an optical fiber fusion splicer according to claim 1, wherein a substrate on which the multistage voltage doubler circuit and the high frequency capacitor are mounted is embedded in an electrically insulating resin.   2. The optical fiber fusion according to claim 1, wherein the substrate on which the multistage voltage doubler circuit and the high frequency capacitor are mounted is embedded in an electrically insulating resin, and the linearly arranged transformer is not embedded in the electrically insulating resin. High-voltage power supply device for connecting machines.

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