JPH0546012U - Grounding device for transformer core - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] Insulate the yoke portion of the winding core protruding from the winding by fitting the winding onto the winding core formed by winding the amorphous magnetic alloy ribbon. The purpose is to ensure that the wound iron core is grounded in a state of being covered with an object. [Structure] Of the pair of reinforcing frames 17 and 18 arranged on the innermost peripheral surface of the winding iron core 27, the winding iron core 27 is provided on the innermost reinforcing frame 18.
And means for making electrical contact with the reinforcing frame 17 of the next layer,
An insulating material that prevents the amorphous magnetic alloy ribbon from peeling off is attached to the yoke portion f of the winding iron core 27 exposed from the winding including the reinforcing frame 17, and the winding is covered with the insulating material. One of the ground terminals is inserted into the yoke portion of the iron core 27 with an insulator penetrating the other, and the other is supported by a clamp attached to the winding iron core 27, and the winding iron core 27 covered with the insulating material also includes the innermost reinforcing frame 18. It is characterized by being able to ground well.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to improvement of a grounding device in a transformer core formed by using an amorphous magnetic alloy ribbon.

[0002]

[Prior Art]

 In recent years, the use of amorphous magnetic alloy ribbons (hereinafter simply referred to as magnetic ribbons) as an iron core material has been gradually increasing in wound iron cores used in stationary induction electric devices such as distribution transformers. This magnetic ribbon is manufactured by ultra-quenching a melt of a magnetic alloy and has a very small iron loss and excellent magnetic properties. Then, for example, in the case of manufacturing a winding core of a distribution transformer by using the winding core made of the magnetic ribbon, a non-cut type winding core having no joint formed by continuously winding the magnetic ribbon is used. After forming and winding the core into a rectangular shape by tightening a core tightening band on the outside and performing magnetic field annealing, the winding is wound directly on the leg iron part, or A plurality of unit cores (several tens of pieces) obtained by cutting the magnetic ribbon for each turn are combined to form a unit laminated core, and the unit laminated core is further laminated into a plurality of layers to form a unit laminated block (hereinafter, simply laminated). In order to assemble the wound core, the laminated block is wound in a circular shape, and both ends of the unit laminated core are sequentially abutted or superposed while being shifted stepwise, and the laminated block is further joined. , Number of layers required Laminate as above After forming the wound cores of one-turn-cut scheme Do a predetermined lamination thickness, performing a magnetic field annealing junction of the butt or the like is positioned on one side of the yoke portion is formed into a rectangular shape. After that, the winding core opens the joint of the yoke section for each laminated block, sequentially inserts each laminated block into the core insertion hole of the winding, and rejoins the joined portion of each laminated block, and then the laminated block. A 1-turn cut type wound core was assembled by winding a tightening band around the outermost circumference of the.

When a transformer is manufactured by using the wound core manufactured by the uncut method or the one-turn cut method, the iron core and Attach a clamp to fix the contents of the transformer consisting of windings, then store the contents of the transformer in a case, and attach the contents fixing metal fittings provided at both ends of the clamp attached to the upper yoke part of the winding core, After fixing and supporting the support brackets formed on the inner wall surface of the case with fixing bolts, the case was filled with insulating oil to manufacture a transformer for distribution. Although the contents of the transformer are housed in the case, the outer surface of the transformer is normally high when the transformer is energized due to the electrostatic capacity existing between the surface and the ground. Since there is a potential for this to cause electric shock when touched or approached by the human body, a grounding terminal is provided on the outer surface of the transformer case, and this grounding terminal is grounded. The problem was solved.

[0004]

[Problems to be solved by the device]

 However, in the above transformer, when the winding core that constitutes the inside of the transformer is grounded to the ground terminal provided on the outer surface of the case, the tightening band that is usually wound around the outer circumference of the winding core is tightened on the clamp. Due to this, the electrification of the winding iron core was led to the ground terminal via the fastening band → clamp → contents fixing metal fitting → case. This is because when the transformer is energized, the high voltage applied to the high voltage winding causes electrostatic induction in the wound core, which results in charging between the wound core and the clamp, or between the low voltage winding, for example. This is to prevent the occurrence of a discharge phenomenon that deteriorates or damages the insulating oil and the insulation on the low-voltage winding side. However, when the wound iron core used for the transformer is formed by winding the magnetic ribbon, the magnetic ribbon has a drawback that it is very thin and has poor rigidity for manufacturing reasons. Since it is extremely weakened by annealing, if the tightening band is tightened around the outer circumference of the wound core after it is assembled in this state, it becomes difficult for the wound core to withstand the tightening force. Despite being annealed, there was a big problem that local mechanical strain was generated or the shape was deformed and the magnetic properties of the wound core were impaired.

Further, since the magnetic ribbon is extremely brittle due to annealing as described above, when the winding is wound around the winding iron core, or the winding iron core is disassembled into blocks and assembled into the winding. In addition, when assembling a transformer using the wound core after assembling the wound core, if an external force is applied to the laminated end surface of the wound core, the corners and the stack of the wound core can be easily The end faces of the layers are chipped or peeled off to generate fragments. If the debris remains in the core insertion hole of the winding after the winding core is assembled, it will stray due to convection of insulating oil during operation of the transformer, and if it enters between the winding layers, There was a problem of causing a short circuit accident.

As described above, when a transformer is manufactured by using a wound iron core wound with a magnetic ribbon, not only the iron core characteristics are deteriorated, but also the manufacturing thereof requires much labor and skill. However, it was difficult to improve the productivity of transformers that effectively utilize the magnetic properties of magnetic ribbons. For this reason, when the magnetic ribbon fragments are peeled off from the wound core, the wound core itself is completely surrounded by an insulator to prevent the fragments from dissipating in the insulating oil. However, if the wound iron core is surrounded by an insulator, there is a problem that the grounding of the voltage transformer is hindered by the insulator and it cannot be satisfactorily performed.

In view of the above-mentioned various problems, the present invention uses a tightening band to satisfactorily bond the ground terminal and the winding iron core even when the winding iron core is completely surrounded by a thin insulating material. The grounding device for the transformer core, which eliminates the adverse effects caused by this, and eliminates the phenomenon of the magnetic ribbon, which is the material of the wound core, peeling off reliably and enables the manufacture of a transformer with excellent core characteristics and mass productivity. The purpose is to provide.

[0008]

[Means for Solving the Problems]

 The present invention uses a magnetic ribbon, for example, a pair of reinforcing frames made of silicon steel strip on the inner peripheral surface of a circular wound iron core wound by a one-turn cut method within a range not forming one turn. Arranged so that the open end sides are mutually staggered and one turn is formed on the outer peripheral surface, and the reinforcing frames are respectively formed by a thick raw steel strip that is thicker than the magnetic strip. Next, after forming the wound core into a rectangular shape and performing magnetic field annealing, a reinforcing frame located on the innermost peripheral surface of the wound core is provided on each straight portion of the yoke portion having no leg iron portion and no joint portion. With the insulation removed, a thin insulator is wrapped around the winding core to provide a stripping-prevention section, and then the yoke section side with the winding core joint is made to have a U-shaped winding core shape. To the corner, and then using the opened yoke part, Insert the leg iron part of the winding core into the iron core insertion hole of the winding inscribed in the state where the protrusion is formed on the outside, and then re-join the opened yoke part to finish the assembly of the winding core. ..

After that, the yoke portion of the winding core exposed on the axial end surface side of the winding is wrapped from the outside with a thin insulator to completely cover the iron core portion. Then, in the covered yoke portion, for example, a copper-made thin ground terminal is provided in the gap of the overlapping portion of the reinforcing frame that reinforces the outer circumference of the wound core at the outer peripheral edge of the yoke portion having the joint portion. Press in about half of that from the outside of the insulator, bend the part of the terminal exposed from the yoke part into a U shape, and press the bent part against the yoke part of the winding core. After that, the grounding terminal is connected to the reinforcing frame on the outer circumference of the winding core covered with thin leaf insulators by fixing it to the clamp attached to the winding core using a set screw. The contents of the transformer with terminals are housed in a case, and the metal fixing bracket provided in the clamp part is fixed to the inner wall of the case to form a wound core transformer. Its operation is as follows.

According to the present invention, in the reinforcing frame located on the innermost peripheral surface of the wound iron core, the projections protruding near the corners of the reinforcing core are brought into contact with the reinforcing frame located on the next layer of the innermost peripheral surface so as to be electrically connected. Since the winding core is assembled, the winding core is assembled in advance in a straight line between the leg iron part and the yoke part of the winding core, including the reinforcing frame of the next layer. Even if a stripping prevention part is provided on the wound iron core by wearing, since the reinforcing frame located on the innermost peripheral surface is provided with a protrusion slightly longer than the thickness of the insulator near the corner part, As a result of the protrusions being in electrical contact with the reinforcing frame located in the next layer in the vicinity of the corners of the winding core where the above-mentioned stripping-preventing portion does not exist, there is a stripping-preventing portion wound around the winding core. In this case, the reinforcing frame located on the innermost peripheral surface and the winding core can be electrically connected well. Wear.

Further, even if the yoke portion of the winding core exposed from the winding is covered with a thin insulating material, the ground terminal is provided on the outer periphery of the winding core from the outside of the covering insulating material. It is configured to press-fit using the narrow gap that is inevitably generated near the overlapping part and to fix the part exposed from the yoke part to the clamp by screwing etc. Coupled with good grounding of the reinforcing frame on the innermost peripheral surface of the iron core, even if the winding core is completely covered with an insulator, the presence of the grounding terminal prevents the winding iron from being charged by the conventional iron core clamping. It is possible to easily lead to the ground terminal through the wound iron core → the grounding terminal → clamp → content fixing bracket → case without using the attached tightening band. Moreover, since the tightening band for tightening the wound iron core itself is not used, it is possible to surely eliminate the harmful effect of using the tightening band.

[0012]

【Example】

 Hereinafter, an example in which the present invention is applied to a one-turn cut type winding core will be described with reference to FIGS. In FIG. 1, reference numeral 11 denotes a winding shaft drivingly connected to a winding machine (not shown). A circular winding frame 12 is detachably attached to the winding shaft 11 and the winding frame 12 is rotated so that the amorphous magnetic Each time an alloy ribbon (hereinafter referred to as a magnetic ribbon) T is wound around the winding frame 12 by the cutting device 13, the magnetic ribbon T is cut in a circular shape a predetermined number of times and cut for one turn. A wound iron core element body 14 that is a prototype of the iron core is formed. When winding the wound core element body 14, the magnetic ribbon single plate cut during winding on the winding frame 12 is wound so as not to fall off from the winding frame 12. A rubber belt (not shown) is wound around the peripheral surface of the iron core body 14 via a guide roller 15.

The circular wound core element body 14 wound as described above is attached to the outermost periphery thereof with, for example, an adhesive tape (not shown), and is removed from the winding shaft 11 together with the winding frame 12. As shown in FIG. 2, the wound iron core element 14 removed from the winder is wound around the outer peripheral surface thereof with a plate thickness larger than that of the magnetic ribbon T, for example, a silicon steel strip slightly over one turn, The overlapping portion is temporarily fixed with an adhesive tape or the like to provide the outer reinforcing frame 16. On the other hand, after removing the winding frame 12 on the inner peripheral surface, as shown in FIG. 2 as well, the inner reinforcing frame 17 (the opening portion a is wound around the core a with a substantially C-shaped plane using a silicon steel strip). It is opposed to the position of the joint b of the element body 14. Further, the reinforcing frame 17 is formed into a U shape by a molding process, and the innermost reinforcing frame (the tip end) is formed into a ring shape within a range where one turn is not formed. The abutting portion c of is positioned on the opposite side of the opening portion a of the inner reinforcing frame 17) and 18 are inserted and arranged to maintain the circular state of the wound core element body 14.

Next, as shown in FIG. 3, the circular wound core element body 14 is pressed by a hydraulic press or the like through the molding plates 19 and 20 simultaneously from the front / rear and left / right directions to extend the length. Transform into a circle. Then, as shown in FIG. 3, the wound core element body 14 is pressed and held in an oval shape, and at a position corresponding to the yoke portion of the wound iron core, a pair of molding dies 21 and 22 are provided. The recessed grooves 23 provided in the grooves 21 and 22 are inserted and arranged so as to face each other, and in this state, a tapered template 24 having a lower end between the recessed grooves 23 and 23 whose length is slightly shorter than the upper end is formed. , 24 (see FIG. 4) are press-fitted between the recessed grooves 23, 23 by a press, and at the same time, the rolled core element body 14 which has been oval-shaped is further pressed by the forming plates 19, 20, and as shown in FIG. Then, it is formed into a rectangular shape. After the wound core element body 14 is formed into a rectangular shape, the forming plates 19 and 20 are fixed to each other using tightening bolts (not shown), and the forming holding frame 25 is formed by forming a rectangular frame as shown in FIG. As a result, the wound core element body 14 can be favorably held in a rectangular shape.

Subsequently, as shown in FIG. 4, a heat resistant electric wire is wound from one leg iron portion d of the wound core element body 14 over the forming and holding frame 25 to thereby excite the magnetic field annealing coil. 26, and then, the wound core body 14 is placed in an annealing furnace filled with an inert gas, and a constant current is applied to the exciting coil 26, and at the same time, magnetic field annealing is performed at a predetermined heating temperature. After the magnetic field annealing, as shown in FIG. 5, the exciting coil 26 is removed from the wound core element body 14, the forming holding frame 25 is disassembled, and further, the concave plates 23 and 23 of the forming dies 21 and 22 are used. By removing 24 and removing it from the wound core element body 14 together with the molding dies 21 and 22, the rectangular holding state of the wound core element body 14 is released to form a wound core 27. As described above, when the magnetic field annealing is performed, the wound iron core 27 is shaped so as to maintain a rectangular state as shown in FIG. 5, and the presence of the inner and outer reinforcing frames 16 to 18 makes it possible to form a good rectangular shape. It becomes possible to retain the state.

Next, from the rectangularly shaped wound iron core 27, only the innermost reinforcing frame 18 that is rectangularly shaped within a range where one turn is not formed is temporarily removed, and in this state, as shown in FIG. In the window of the wound core 27, the second molding dies 28, 29 are arranged on the yoke portion e, f side, and the plate-shaped template 30 is placed between the second molding dies 28, 29. The recessed groove 30a is used for press fitting to prevent the wound iron core 27 from losing its shape due to an external force. After the winding iron core 27 is treated by the second molding dies 28 and 29 and the mold plate 30 so as not to lose its shape, as shown in FIG. Then, for example, a room temperature curable adhesive is applied at a plurality of positions in the length direction of the leg iron portion d at a predetermined interval to form the adhesive portion 31. After the adhesive portion 31 is formed, before the adhesive is cured as shown in FIG. 7, the adhesive portion 31 is provided with a length substantially corresponding to the length dimension of the straight line of the leg iron portion d, and is folded in a U shape in the width direction. An adhesive similar to the above is applied to the bent inner side of the relatively thin insulating paper, and the insulating paper is applied to the reinforcing frame 16 inside and outside almost all of the leg iron part d 1 from the vertical direction of the laminated end surface of the leg iron part d 1. Wrap and stick together, including 17 together.

For the insulating paper, the adhesive applied to the insulating paper itself and the adhesive already applied to the laminated end face side of the leg iron part d are well adapted to each other, and the insulating paper should be immovably attached to the leg iron part d. Can In this way, the laminated iron end face of the wound iron core 27 is damaged by the external impact of the laminated end face of the leg iron part d, or the magnetic ribbon which is fragile due to the impact of a jig or the like upon annealing. A peeling-off preventing portion 32 is formed to prevent the peeling-off or peeling-off. The adhesive portion 31 is formed on the leg iron portion d to prevent the peeling prevention portion 32 from moving. Therefore, it is not necessary to provide the adhesive portion 31 on the entire leg iron portion d. Then, after the exfoliation prevention part 32 is formed on the leg iron part d, the second molding dies 28 and 29 and the mold plate 30 are removed from the wound iron core 27. Also, of the yoke portions e and f of the winding iron core 27, a thin leaf insulating paper having a length substantially equivalent to the length dimension of the straight portion is also provided on the yoke portion f side having no joint b. As shown in FIG. 8, it is wound around the yoke portion f and temporarily fixed with a tape or the like to form the original shape of the peeling prevention portion 32a in the yoke portion f.

As described above, when the stripping prevention portions 32 and 32a are formed on the leg iron portion d and the yoke portion f of the winding iron core 27, the linear portions of the leg iron portion d and the yoke portion f of the winding iron core 27 become It is possible to prevent the laminated end surfaces from peeling off, and also to enhance the rigidity of the leg iron portion d and the leg iron portion f in combination with the presence of the inner and outer reinforcing frames 16 and 17. .. In such a state, the temporary fixing of the overlapping portion (the upper end surface of the upper yoke portion e of the winding core 27) of the outer reinforcing frame 16 is temporarily released. In this case, since the reinforcing frame 16 is annealed at the annealing temperature of the magnetic ribbon T which is about half the annealing temperature of itself, the elastic force of the material itself remains, so that the reinforcing frame 16 can be easily opened and the wound iron core can be released. It can be expanded to a position almost on the same line as the leg iron part d of 27. On the other hand, in the wound iron core 27 around which the magnetic ribbon T is wound, the yoke portion e where the joining portion b is located is changed from the rectangular state in FIG. 7 to the leg portion d as shown in FIG. It is opened so that the planar shape is U-shaped up to a position substantially on the same line. The opening work of the yoke portion e described above is performed by removing the stripping prevention portions 32 and 32a formed on the leg iron portion d and the yoke portion f of the winding iron core 27 and the reinforcing frame 16 and the inner circumference arranged on the outer peripheral surface of the winding iron core 27. The U-shaped inner reinforcing frame 17 arranged on the surface of the winding iron core 27 maintains sufficient rigidity, so that the winding iron core 27 can be smoothly and satisfactorily U-shaped without being deformed by its own weight or deformed. Can be opened in a shape.

On the other hand, as shown in FIG. 8, the winding 34 incorporated in the winding iron core 27 is provided with the innermost reinforcing frame 18 removed when the peeling prevention portion 32 is formed on the leg iron portion d of the winding iron core 27. As shown in FIG. 8, the iron core is fitted into the innermost side of the insertion hole 35 in a rectangular shape. As shown in FIG. 13, the innermost reinforcing frame 18 is provided with a plurality of protrusions P on the outer peripheral surface side in proximity to the corners of the four corners. The projection P is formed by using a simple press or a punch after removing the innermost reinforcing frame 18 when the peeling prevention portion 32 is formed on the leg iron portion d of the winding iron core 27, or by the innermost reinforcement. It may be formed in advance when the frame 18 is in a flat plate shape before being rectangularly formed. Further, as shown in FIG. 8, when the protrusion P is provided with the stripping prevention portions 32, 32a, the position where the projection P is provided is not covered with the insulator existing between the stripping prevention portions 32, 32a. That is, it is formed at a position corresponding to the vicinity of the inner corner of the wound iron core 27. Further, the protrusion length of the protrusion P is set to be slightly longer than the wall thickness of the exfoliation prevention portions 32 and 32a.

As described above, in the state where the innermost reinforcing frame 18 having the projection P near the corner is inscribed in the iron core insertion hole 35 of the winding 34, the wound iron core 27 opened in the U-shape. As shown in FIG. 8, the opened joint portion b of the yoke portion e faces the iron core insertion hole 35 of the winding wire 34, and the joint portion b of the wound iron core 27 is inserted into the iron core insertion hole 35 of the winding wire 34. When the winding core 27 is inserted from the side provided with the yoke portion e, the stripping prevention portion 32 slides into contact with the innermost reinforcing frame 18 and the winding core 27 is assembled into the winding wire 34 from the yoke portion e to the leg iron portion d in almost one operation. You can

As shown in FIG. 9, the winding core 27 opened in the U shape is fitted into the winding 34, and then, on the outer surface of the innermost reinforcing frame 18 located on the open end side of the winding core 27, The insulating paper 18a surrounding the linear portion of the yoke portion e of the winding iron core 27 is attached, and the space between the axial end portion of the winding wire 34 and the innermost reinforcing frame 18 is shown in FIG. As described above, the spacers 36 and 37 made of an insulating material are inserted, and then the yoke portion e of the opened wound iron core 27 is sequentially bent from the innermost layer portion to the state (inner side) before opening, and the opening is performed. The pieces g are joined together as shown in FIG. 10 to re-form the joint b. Then, the free end of the outer reinforcing frame 16 arranged on the outer periphery of the wound iron core 27 is superposed on the outer peripheral surface of the yoke portion e where the joint b is located, and the end of this portion is fixed by spot welding or the like. An adhesive is appropriately applied to the laminated end surface of the yoke portion e to attach the insulating paper 18a from the laminated end surface of the yoke portion e toward the outer peripheral side thereof as shown in FIG. To form. In addition, the thin insulating paper temporarily fixed to the other yoke portion f side of the winding core 27 is also adhered by applying an adhesive to the laminated end surface of the yoke portion f in the same manner as described above, and the peeling prevention portion 32a is attached. By forming, the assembly work of the winding iron core 27 to the winding wire 34 is completed as shown in FIGS. After fixing the overlapped portion of the outer reinforcing portion 16 and forming the peeling prevention portions 32a and 32b, the wedge 38 is press-fitted into the gap between the spacer 36 and the innermost reinforcing frame 18 and wound. The wire 34 is fixed in the window of the winding core 27.

When the winding iron core is assembled as described above, the innermost reinforcing frame 18 located in the innermost layer of the winding iron core 27, which plays a role of reinforcing the yoke portion e side of the winding iron core 27, and the outside The relationship with the reinforcing frame 17 of the next layer to be positioned is that the stripping prevention portions 32, 32a, 32b provided by winding an insulator around the leg iron portion d and the yoke portions e, f of the winding iron core 27 and the reinforcement of the next layer. By virtue of the presence of the frame 17, the innermost reinforcing frame 18 has four corners, as shown in FIG. 11, and the corners of the winding core 27 and the reinforcing frame 17 of the next layer corresponding to the corners. In the gap, a minute gap s ₁ is generated due to the wall thickness of the peeling prevention portions 32, 32a, 32b and the reinforcing frame 17. However, the portion of the innermost reinforcing frame 18 corresponding to the leg portions d of the winding iron core 27 and the straight portions of the yoke portions e and f makes good contact with the winding iron core 27, but this portion is made of an insulator. Since the exfoliation preventing portions 32, 32a, 32b are present, it is difficult to directly contact the wound iron core 27. Therefore, only the innermost reinforcing frame 18 may not be able to be grounded integrally with the wound iron core 27. However, in the present proposal, as shown in FIG. A plurality of protrusions P projecting toward the gap s ₁ are formed, and when the protrusions P have finished assembling the wound iron core 27, as shown in the enlarged sectional view of FIG. 32, 32a, and 32b do not exist (in the vicinity of the inner corner of the wound iron core 27), they come into direct contact with the reinforcing frame 17 of the next layer, so that only the innermost reinforcing frame 18 is provided. It is possible to surely solve the problem of being unable to ground. Further, when the outer reinforcing frame 16 is fastened by overlapping its free ends with each other on the outer peripheral surface of the yoke portion e having the joint portion b of the winding iron core 27, as shown in FIG. It is possible to form a narrow gap s between the r edge and the upper end surface of the yoke portion e.

As described above, after the winding iron core 27 is inserted into the winding wire 34 as shown in FIG. 12, the winding iron core 27 is assembled, and then the whole yoke portions e and f of the winding iron core 27 are covered with a thin leaf insulating material 39. Wrap it up and cover it as shown in FIG. The thin-walled insulator 39 is excellent in heat resistance and flexibility so that it can be well wrapped around the yoke portions e and f of the winding core 27 having an arcuate portion, and is excellent in insulation. A non-woven fabric made of synthetic fibers with a high degree of porosity that is well adapted to oil is used.

When wrapping the thin-walled insulator 39, the insulator 39 is preliminarily formed into a rectangular shape in such an area that the laminated end face and the outer peripheral edge can be integrally wrapped in each of the yoke portions e and f. Then, the cut insulator 39 is bent into a U shape while being applied to the outer peripheral surface of the yoke portion e, and the bent piece is brought into contact with the yoke portion e side. As shown in FIG. 15, the portion protruding to the outer peripheral edge side is bent from the laminated end face side of the yoke portion e toward the outer peripheral edge side, and the bent portion is attached to the outer peripheral edge of the winding iron core 27 with an adhesive tape. The yoke portion e is completely covered with the thin-walled insulator 39 by, for example, attaching. When the covering of the yoke portion e with the insulator 39 is completed, the other yoke portion f is also coated with the insulator 39 as described above. When the insulator 39 is coated on the yoke portions e, f, an adhesive or the like is appropriately applied to the laminated end surfaces of the yoke portions e, f in advance, and then the wrapping operation is started, so that the insulator It is possible to smoothly and satisfactorily cover the 39 yoke portions e and f. Further, after the insulator 39 is wrapped, an insulating varnish or the like may be applied from above the insulator 39 to prevent the insulator 39 covering the yoke portions e and f from coming off.

After covering the yoke portions e and f of the wound core 27 with a thin insulator 39, an adhesive is applied to the outer peripheral surface of the wound core 27 in a semi-cured state, as shown in FIG. The adhesive insulating paper 40 is wound around the iron core insertion hole 35 of the winding wire 34 to prevent the bent portion of the thin insulating material 39 from peeling outward. Thereafter, a thick guide plate (not shown) such as a press board is provided outside the adhesive insulating paper 40 in a small gap (not shown) existing between the outside of the leg iron portion d of the winding iron core 27 and the winding 34. Is press-fitted to the center position of the winding iron core 27 in the width direction. As a result, the winding 34 can be fixed to the winding iron core 27 by the guide plate, spacers 36, 37, and wedge 38 (not shown) without swinging. As described above, the wound iron core 27 includes the reinforcing frames 16, 17 and 18 arranged on the outer peripheral surface thereof, and the peeling prevention portion 32 wound around the straight portions of the leg iron portion d 1 and the yoke portions e and f. 32a, 32b and the thin-walled insulator 39 attached to the yoke portions e, f so as to surround the yoke portions e, f strengthens the rigidity and prevents the peeling-off, so that an impact due to an external force or It is possible to reliably prevent the wound iron core 27 from being deformed by its own weight due to vibration or the like, and the fragments of the magnetic ribbon T from being scattered to the outside.

Next, a gap s formed between the overlapping edge r of the outer reinforcing frame 16 disposed on the outer peripheral surface of the winding core 27 on the side of the upper yoke portion e and the upper end surface of the yoke portion e. Then, as shown in FIG. 16, the ground terminal 41 is pressed through the insulator 39 by a length of about 1/3. After press-fitting the ground terminal 41, an adhesive or the like is applied to the damaged portion of the insulator 39 to prevent the fragments of the magnetic ribbon T from scattering outside from the damaged portion. After that, as shown in FIG. 17, the ground terminal 41 press-fitted into the gap s of the outer reinforcing frame 16 has a portion projecting on the surface of the yoke portion e of the winding core 27 on the thin-walled insulator 39. In the state where the horizontal protruding portion P having a constant length is left, the yoke portion e is bent in a U shape to form an engaging portion t with a clamp described later.

After press-fitting the ground terminal 41, as shown in FIG. 18, the winding iron core 27 incorporated in the winding wire 34 is raised, and in this state, the laminated end surface of the winding iron core 27 has a plate-like winding made of an insulating material. The wire retainer 42 is applied by abutting on the upper and lower end surfaces of the winding 34 in the axial direction. In this case, as shown in FIG. 18, the winding presser 42 is formed such that its height is slightly higher than the outer peripheral surfaces of the yoke portions e and f of the winding iron core 27, and the ground terminal Reference numeral 41 denotes a U-shaped engaging portion t located outside the winding retainer 42 by engaging a protruding portion o with a notch hole 43 notched at a position where the ground terminal 41 of the winding retainer 42 protrudes. Is formed.

When the above-mentioned clamp is attached to the winding core 27, the upper clamp 44 and the lower clamp 45, which are wider than the width dimension of the winding core 27 and are formed into a U-shape, are respectively attached to the yoke portions of the winding core 27. As shown in FIG. 19, play is made from the vertical direction of e and f. In this case, since the ground terminal 41 has the U-shaped engaging portion t, when the upper clamp 44 is loosely engaged, one of the bent pieces is favorably engaged with the engaging portion t of the ground terminal 41. Can be installed. The upper and lower clamps 44 and 45 have a constant length with respect to the outer peripheral surface of the winding iron core 27 because the winding retainer 42 is formed so as to project from the outer peripheral surface of the winding iron core 27. It becomes possible to play and hold it while keeping it floating. Then, after the upper and lower clamps 44 and 45 are loosely fitted to the winding iron core 27, as shown in FIG. 19, a clamp tightening band 46 is drilled from the lower side of the lower clamp 45 to a through hole 47 formed in the lower clamp 45. And vertically penetrates a gap formed by a guide plate (not shown) press-fitted into the leg iron portion d of the winding iron core 27 between the winding iron core 27 and the winding 34, and as it is, from the through hole 47 of the upper clamp 44 to the winding iron core 27. The upper and lower clamps 44 and 45 are firmly fixed to and supported by the tightening band 46 via the winding retainer 42 on the winding 34 by projecting them upward and tightening them on the upper clamp 44. .. As a result, the wound iron core 27 can be held on the winding 34 in a non-pivotable manner without any mechanical stress due to the attachment of the upper and lower clamps 44 and 45 due to the interposition of the winding retainer 42.

After attaching the upper and lower clamps 44 and 45, the free end of the engaging portion t 1 of the ground terminal 41 is fixed to the bent portion of the upper clamp 44 by using a set screw 50 to transform the transformer. The assembly of the container contents 51 is completed. As a result, in the ground terminal 41, even if the yoke portions e and f projecting from the winding 34 of the winding iron core 27 are entirely covered with the thin leaf insulator 39, the innermost reinforcing frame 18 However, even if an insulator partially intervenes between it and the reinforcing frame 17 of the next layer, the entire wound iron core 27 and the upper clamp 44 can be connected to each other so that they can be accurately grounded. As shown in FIG. 19, the transformer contents 51 constructed as described above are provided with the contents fixing metal fittings 52 attached to both ends of the upper clamp 44 in the length direction on the inner wall of the case (not shown). By tightening the mounting seat with the tightening bolt, the transformer contents 51 housed in the case can be securely fixed to the case. Therefore, the electrification of the winding iron core 27 that occurs during the operation of the transformer is favorably guided to the ground terminal 41 crimped to the winding iron core 27 → the upper clamp 44 → the content fixing bracket 52 → the case → the earth terminal provided on the case. It can be flushed to the ground.

Note that, in FIG. 20, instead of providing the protrusion P near the corner portion of the innermost reinforcing frame 18, the conductive tape R is attached across both sides of the corner portion of the innermost reinforcing frame 18, The present invention can be realized even if the innermost reinforcing frame 18 and the reinforcing frame 17 located in the next layer are electrically connected by the tape R.

[0031]

[Effect of the device]

 According to the present invention, when a one-turn cut type winding core is incorporated in a winding, the material of the winding core is an amorphous magnetic alloy thin strip having a thickness of about 1/10 that of a silicon steel strip. As a result, the winding core itself is opened in a U-shape and inserted into the winding by using the joint of the winding core. Therefore, the winding core maintains its rigidity on its inner and outer peripheral surfaces. A U-shaped reinforcing frame for the purpose is integrally provided in the straight portion of the leg iron portion and the yoke portion by winding the insulating member. On the winding side, on the other hand, when the yoke parts of the open wound core are rejoined, the innermost reinforcement frame for reinforcing that part is placed in advance, so the wound core is wound. , The innermost reinforcing frame arranged on the winding side and the inner reinforcing frame arranged on the winding core side are electrically connected by the insulating member partially interposed between them. Connection becomes difficult, and partial discharge occurs during operation of the transformer in the space between the innermost reinforcing frame and the inner reinforcing frame, which causes abnormal noise and deteriorates and damages the winding insulation. There is a risk of causing problems. However, since the innermost reinforcing frame is provided with means for electrically connecting to the inner reinforcing frame by providing a protrusion on a portion where no insulating member is interposed or by attaching a conductive tape, The innermost reinforcing frame can be reliably grounded to the winding iron core. Therefore, as described above, it is possible to provide a transformer core excellent in iron core characteristics in which partial discharge does not occur at all and adverse effects due to partial discharge occur at all.

Further, the present invention employs a structure in which a yoke portion covered with a thin-walled insulating material is passed through the insulating material so that the ground terminal itself directly contacts the wound iron core. In addition to the point that the innermost reinforcing frame of the winding core is properly grounded with the winding core as described above, the winding core whose outer surface is covered with the insulator is smoothly and satisfactorily grounded. You can

[Brief description of drawings]

FIG. 1 is a schematic view showing a winding state of an amorphous magnetic alloy ribbon.

FIG. 2 is a plan view of a wound core element body wound in a circular shape.

FIG. 3 is an explanatory diagram showing a process of forming a wound core element body.

FIG. 4 is an explanatory diagram showing a state where a wound core element body is rectangularly formed and an annealing treatment is performed.

FIG. 5 is a plan view of a wound iron core that is annealed and shaped into a rectangular shape.

FIG. 6 is an explanatory view showing a process of forming an insulating reinforcing portion formed on a leg iron portion of a wound iron core.

FIG. 7 is a plan view of a wound iron core in which an insulation reinforcing portion is formed on a leg iron portion.

FIG. 8 is an explanatory diagram showing a case where a winding is incorporated into a wound iron core opened in a U shape.

FIG. 9 is an explanatory view showing a state in which a winding is inserted in a wound iron core opened in a U shape.

FIG. 10 is an explanatory view showing the process of assembling the wound core.

FIG. 11 is an explanatory diagram showing a state in which a winding wire is incorporated in a winding iron core.

FIG. 12 is a perspective view showing a state in which the wound core is completely assembled.

FIG. 13 is a perspective view of an innermost reinforcing frame.

FIG. 14 is an enlarged cross-sectional view of a main part of a wound iron core.

FIG. 15 is an explanatory diagram showing a state in which the entire area of a yoke portion of a wound iron core incorporated in a winding wire is covered.

FIG. 16 is an exploded perspective view showing a state in which a grounding terminal of the present invention is attached to a wound iron core.

FIG. 17 is a perspective view of a wound core showing a mounting state of a ground terminal according to the present invention.

FIG. 18 is a perspective view showing an assembling process of the wound core transformer.

FIG. 19 is a perspective view of a wound core transformer showing a mounting state of a ground terminal according to the present invention.

FIG. 20 is a perspective view showing another embodiment of the innermost reinforcing frame.

[Explanation of symbols]

16 Inner Reinforcement Frame 17 Outer Reinforcement Frame 18 Innermost Reinforcement Frame 18a Insulating Paper 27 Winding Iron Core 32 Detachment Blocking Part 32a Detachment Blocking Part 32b Detachment Blocking Part 34 Winding 39 Insulation 41 Grounding Terminal 44 Upper Clamp 45 Lower Clamp 46 Tightening Band 50 Set screw b Joint part d Leg iron part e Yoke iron part f Yoke iron part P Protrusion s Gap s ₁ Gap R Conductive tape

Claims (2)

[Scope of utility model registration request] 1. A transformer in which a winding is fitted to a wound core formed by winding an amorphous magnetic alloy ribbon a predetermined number of times,
In the innermost layer of the wound core, a pair of reinforcing frames made of a silicon steel strip is arranged within a range not forming one turn, and when an insulator is partially interposed between the pair of reinforcing frames, The innermost reinforcing frame of the pair of reinforcing frames is provided with a corresponding reinforcing frame at a portion where the insulator is not interposed, or means for electrically connecting with the wound core to form the innermost reinforcing frame. The frame and the winding core are connected to each other so that they can be grounded, and the portion exposed from the winding portion of the winding core is covered with a thin leaf insulating material, and the winding iron core covered with the insulating material is connected to one of the ground terminals. A grounding device for a transformer core, wherein an end is press-fitted, and a free end, which is the other end of the grounding terminal, is fixed to a clamp attached to a yoke portion of the winding core. 2. The means for electrically connecting between the innermost reinforcing frame and the reinforcing frame located in the next layer or the wound core is either the innermost reinforcing frame or the next layer reinforcing frame. A grounding device for a transformer core, characterized in that one side is provided with an electrical connecting means composed of a protrusion or a conductive tape.