JP2009054927A - Stationary induction electric apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stationary induction electric apparatus where a butting clearance gap dimension of a junction part of an iron core is managed without impairing workability. <P>SOLUTION: The stationary induction electric apparatus is provided with: a rectangular iron core composed by jointing two sets of U-shaped iron core members each formed of a stacked magnetic steel sheet to each other by an iron core leg part; a coil inserted into the iron core leg part; and a fitting supporting the iron core. The stationary induction electric apparatus is characterized by being provided with a restriction part forcibly restricting a butting clearance gap dimension or a superposition margin dimension of a junction part of the two sets of U-shaped iron core members. The restriction part may be an outer height restriction member provided for the fitting to restrict the outer height of the iron core, or an inner height restriction member inserted in an end surface of the coil and the inner surface of a window of the iron core to restrict the inner height in the window of the iron core. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a static induction device such as a transformer or a current transformer, and more particularly to a static induction device that joins two sets of U-shaped core members with core legs.

  In general, in a transformer in which two sets of U-shaped core members are joined by core legs, coils are inserted into the core legs, and various structures are employed from the viewpoint of improving magnetic characteristics and workability. In Patent Document 1, as shown in FIG. 1, a silicon steel strip 1 (electromagnetic steel sheet) is spirally wound to form a substantially rectangular shape, and then the center of both left and right leg portions is cut along the axial direction. Then, the cut surface was polished, and then the coil was inserted and the cut surface was bonded and butt-bonded to form an integral wound core. A structure similar to this structure is also described in Patent Documents 2 and 3.

  Moreover, as shown in FIG. 2 and FIG. 3 of Patent Document 1, a plurality of silicon steel strips having different lengths are overlapped with their ends shifted, and set in a lower mold, and then inverted U-shaped. The upper die of the shape is pressed with a cylinder and press-molded, and as shown in FIG. Then, the iron core member is made into a two-component type, the coil 4 is inserted and combined, and the end side surfaces of the joining surface 3 are overlapped and joined (lap joining) stepwise as shown in FIG.

  Further, as shown in FIGS. 5 and 6, a silicon steel strip is spirally wound around the winding mold to form a substantially rectangular shape, and both legs of the iron core are cut obliquely from the inside to the outside. The core members are separated into individual core members, and then the layers of both core members are inserted and combined into a coil while being reversed horizontally for each layer. As shown in FIG. 6, both the leg portions of the iron core are overlapped and joined between adjacent layers with the joining portions of the respective layers shifted in an X shape.

JP 60-214516 A JP-A-51-59318 JP 58-68916 A

  However, in the wound iron core shown in FIG. 1 of Patent Document 1, the workability is poor because the two legs of the iron core are cut and then combined after polishing, and the joint surface is a butt joint, so a gap is easily formed. The flow of magnetic flux is interrupted and the magnetic properties are deteriorated. In addition, the structure shown in FIGS. 2 and 3 of the same document improves the magnetic characteristics, but cuts the silicon steel strips to predetermined dimensions, shifts the positions accurately, and forms the upper and lower molds after lamination. At this time, the laminated state tends to be shifted and the shift width of the end portion is likely to be non-uniform. Therefore, it is impossible to manage the butt gap size of the joint portion or the overlap margin, and the magnetic characteristics cannot be kept uniform. Furthermore, in the structure shown in FIGS. 5 and 6 of the same document, the magnetic characteristics are also improved, but the layers of both core members are inserted into the coil and combined together while being reversed left and right for each layer. Therefore, there was a problem that workability was poor.

  In addition, in any of the above prior arts, since the joint part of the iron core is on the iron core leg part to which the coil is mounted and cannot be visually observed, it is impossible to accurately grasp the butt gap size or the overlap allowance dimension of the joint part of the iron core member. There is a problem that the magnetic properties of the iron core cannot be controlled uniformly.

  In view of the above-described problems of the prior art, the present invention provides a stationary induction device in which the size of a butt gap of a joint portion of an iron core is managed without deteriorating workability.

  In order to solve the above problems, the present invention provides a rectangular iron core formed by joining two sets of U-shaped iron core members made of laminated electromagnetic steel plates at an iron core leg, and the iron core leg. In a static induction electrical apparatus provided with an inserted coil and a metal fitting that supports the iron core, a restriction portion that forcibly restricts the butt gap size of the joint portion of the two sets of U-shaped iron core members is provided. And

  The constraining portion may be an outer height constraining member provided on the metal fitting so as to constrain the outer height of the iron core, and the end face of the coil so as to constrain the inner height in the window of the iron core. And an inner height restricting member inserted into the inner surface of the iron core window.

  In addition, an uneven portion may be provided in each electromagnetic steel sheet so that adjacent electromagnetic steel sheets are unevenly connected so that the electromagnetic steel sheets laminated with the iron core do not deviate from each other. Each electromagnetic steel sheet may be provided with a stopper hole or a stopper notch so as not to be displaced from each other.

  According to the present invention, the butt gap size or the overlap margin size of the iron core joint can be accurately maintained, so that the magnetic characteristics of the stationary induction device can be accurately controlled.

  Examples of the present invention will be described below. First, the structure of the butt portion of the iron core will be described with reference to FIGS. FIG. 1 is a front view of a rectangular iron core 2 in a state where silicon steel plates 1 (electromagnetic steel plates) are laminated, and FIG. 2 is a side view thereof. In FIG. 1, 1a is a U-shaped upper silicon steel plate, 1b is a U-shaped lower silicon steel plate, and 3a is a joint of the end portions of the silicon steel plate 1 at the legs 3 of the upper and lower silicon steel plates. The seam 3a is not brought into contact with each other and is shifted as shown in FIG. 2 so as to provide a gap 1c.

  FIG. 3 is an enlarged view of the leg 3 of the silicon steel plate shown in FIG. 1, in which the seam 3a is configured by a butt method, and a gap of height E is formed in the seam 3a at the end of each turn. Is provided. FIG. 4 is also an enlarged view, but the seam 3a is configured by a superposition method. Both ends of each turn are overlapped seams 3a, and the end is the start of the next turn. It is comprised so that it may have a predetermined clearance gap. The filled portion indicates an insulator.

  The arrangement in the core leg 3 of the joint 3a of the two types described above will be described with reference to FIGS. FIG. 5 shows an arrangement in which the seam 3a is shifted stepwise within the range of the straight line portion 4 where the coil of the iron core 2 is arranged, and after reaching the end of the straight line portion 4, it is returned to the initial position. FIG. 6 shows an arrangement in which when reaching the end of the straight line portion 4, it is folded back in the opposite direction.

  FIG. 7 is an enlarged view of the U-shaped upper silicon steel plate 1a of the iron core 2 shown in FIG. 1, and FIG. 8 is an enlarged view of the U-shaped lower silicon steel plate 1b of the iron core 2 as well. The silicon steel plates 1a and 1b are cut into a U-shape with different lengths in a straight line before being formed. That is, after the upper silicon steel sheet 1a is formed into a U-shape, it is cut one by one so that the height of the outermost steel sheet of the leg portion is lowered to B and to the inner side in the same length and stepwise. The lower silicon steel plate 1b is formed in a U-shape so that the height of the outermost steel plate of the leg portion is C, and the height is increased stepwise in the same length toward the inside. Cut one by one.

  Further, each of the silicon steel plates 1a and 1b has an uneven portion 1d formed by punching at the ceiling and bottom. The uneven portion 1d is press-formed on a steel plate in a straight line state, and when forming into a U-shape, adjacent steel plates are fitted to each other by a concave portion and a convex portion so as not to be displaced. By preventing this shift, the end portions of the silicon steel plates 1a and 1b can be managed so as to be sequentially different in steps with the same length. The laminated thickness of the steel sheet after forming is indicated by D.

  FIG. 9 is an assembly diagram in which the legs 3 of the upper silicon steel plate 1a and the lower silicon steel plate 1b shown in FIGS. 7 and 8 are inserted into the current coil 8 and combined. Reference numeral 5 denotes a metal fitting that supports the upper silicon steel plate 1a, 7 denotes a metal fitting that supports the lower silicon steel plate 1b, and 6 denotes a member that is interposed between the metal fittings 5 and 7 and connects the two. The outer height dimension F of the iron core 2 is the sum of the height dimension B of the upper silicon steel sheet 1a, the height dimension C of the lower silicon steel sheet 1b, and the dimension E of the joint 3a shown in FIG. In order to enforce this dimension, the member 6 is provided as an outer height restricting member.

  As shown in FIG. 9, the height G of the iron core window 4, which is the inner height of the iron core 2, is the height H of the coil 8, and the height of the members 9 and 10 interposed between the upper and lower ends of the coil 8 and the inside of the window 4. The total value of J1 and J2. The members 9 and 10 serve as inner height restricting members that forcibly restrict the inner height of the iron core. This restricting member is made of a sheet metal material, insulating paper, synthetic resin or the like, and has a wedge shape, and the height is adjusted by driving.

  When the outer side of the iron core is pressed from above and below by the restriction member 6, the height of the gap E between the steel plates 1 of the iron core is reduced, but the pressing force on the inner steel plate 1 is increased and the U-shaped shoulder is crushed. As such, the height of the gap E between the inner steel plates 1 becomes smaller, and it is difficult to make the gap E between the inner and outer steel plates 1 uniform. On the other hand, when the inner side of the iron core is pressed up and down by the restriction members 5 and 7, the inner steel plate 1 tends to spread, and therefore the height of the gap E between the inner steel plates 1 tends to increase.

  In this embodiment, the height H of the coil 8 and the inner height G after forming the iron core 2 are grasped in advance, and the outer height restriction member 6 restricts the outer height of the steel sheet 1 from the outside. By restricting the inner height from the inner side by the inner restricting members 9 and 10, the height of the gap E between the steel plates 1 from the outer side to the inner side is arbitrarily and almost uniformly managed.

  FIG. 10 shows an example in which the iron core 2 is fixed to the metal fitting 5 with a steel band 11 instead of the height restricting member 6 shown in FIG. FIG. 11 is an enlarged cross-sectional view of the core leg G of FIG. 10, and includes an inner member 12 and an outer member 13 for closely attaching the seams of the laminated silicon steel plates 1 in the thickness direction of the steel plate 1. ing. The adhesive 14 is applied to the joint between the upper silicon steel plate 1a and the lower silicon steel plate 1b, and the inner member 13 and the outer member 12 are pressed from the inside and outside of the core leg to fix the steel plate 1 joint.

  12 and 13 are explanatory views of a state in which the cut steel plates 1 are stacked. In FIG. 12, a round hole 15 for preventing slippage is formed in each steel plate 1b. While the steel plates 1b are stacked, the iron core 2 is formed in a U shape while being inserted into the round holes 15 and inserting a round bar or the like. Can be obtained. FIG. 13 is an example having a notch 16 instead of the round bar 15. At the time of forming, as shown in FIG. 12, it is formed while communicating with each notch 16 and fitting each steel plate 1b with a round bar or elongated projection.

  As described above, according to the embodiment, when two sets of U-shaped iron cores are joined by the core leg portions, the butt gap between the joint portions of the steel plates that are the core members by the outer height restricting member and the inner height restricting member. You can manage the dimensions. Moreover, when laminating steel sheets cut into predetermined dimensions and forming them into a U-shape, the steel sheets are not displaced from each other, and the gap dimensions of the butt portions of the legs of the iron core can be kept uniform for each steel sheet. . Therefore, it is possible to manage the characteristics by appropriately controlling the iron core characteristics (magnetic characteristics).

The front view of the silicon steel plate lamination rectangle forming iron core of the example of the present invention. Similarly side view. The elements on larger scale of the leg part of the silicon steel plate shown in FIG. The elements on larger scale of the superposition method of the leg part of the silicon steel plate shown in FIG. Explanatory drawing of the example shifted to the staircase shape of the butted part of an iron core leg part. Explanatory drawing of the example which shifted the zigzag pattern similarly. The enlarged view of the upper side silicon steel plate of the iron core shown in FIG. Similarly the enlarged view of a lower silicon steel plate. Assembly drawing of iron core and current coil. Explanatory drawing of the example which fixed the iron core with the steel band. The cross-sectional enlarged view of the iron core leg part of FIG. Explanatory drawing of the lamination | stacking state of the steel plate which has a round hole. Explanatory drawing of the lamination | stacking state of the steel plate which has a notch.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Silicon steel plate, 2 ... Iron core, 3 ... Silicon steel plate edge joint, 4 ... Iron core window, 5 ... Upper metal fitting, 6 ... Restriction member, iron core outer side height restriction member, 7 ... Lower metal fitting, 8 ... Coil, 9 ... Restriction member, inner height restriction member, 10 ... Restriction member, inner height restriction member, 11 ... Steel band, 12 ... Inner member for adhesion, 13 ... Outer member for adhesion, 14 ... Adhesive, 15 ... Round hole , 16 ... Notch.

Claims (6)

A rectangular iron core formed by joining two sets of U-shaped iron core members made of laminated electromagnetic steel plates with an iron core leg, a coil inserted into the iron core leg, and a metal fitting for supporting the iron core In static induction electrical equipment
A stationary induction electrical apparatus comprising a restriction member for forcibly restricting a butt gap size of a joint portion of the two sets of U-shaped core members.   The stationary induction electrical device according to claim 1, wherein the restriction member is an outer height restriction member provided on the metal fitting so as to restrict an outer height of the iron core.   The said restriction member is an inner height restriction member inserted in the end surface of the said coil and the inner surface of the said iron core window so that inner height inside the window of the said iron core may be restricted. Static induction electrical equipment as described in.   The inner member and the outer member which make the junction part of the said 2 sets of U-shaped iron core members in the said iron core leg part contact | adhere in the plate | board thickness direction of a steel plate are provided. Static induction electrical equipment.   5. An uneven part is provided in each electromagnetic steel sheet so that adjacent electromagnetic steel sheets are unevenly connected so that the electromagnetic steel sheets laminated with the iron core do not deviate from each other. Static induction electrical equipment as described in.   6. Each of the electrical steel sheets is provided with a stopper hole or a stopper notch so that the electrical steel sheets on which the iron cores are stacked are not displaced from each other. Static induction electrical equipment.

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