JPH02230706A - Transformer core, transformer and manufacture of transformer - Google Patents

Abstract

PURPOSE: To eliminate core other lamination error when contacting the end part of the laminated board on one side of cut laminated boards in the case the cut laminated plates are again connected with each other, of the cut laminated plate by a method wherein when a laminated plate is cut, the laminated plate is cut at a cutting angle, which is not rectangular but slant to the center line in the longitudinal direction of the laminated plate. CONSTITUTION: The positions of the blades 35 and 36 of a cutter 33 are changed at an angle X to a center line 41 and a step 31 between the uppermost group of a laminated plate and the third group of the laminated plate is cut. After that, the positions of the blades 35 and 36 of the cutter 33 are again changed at an angle Y to the center line and a step between the uppermost group and the fourth group of the laminated plate is cut. A core is opened by a mechanical handling and after that, the core is changed into a desirable shape for stress-relieve using an annealing and is closed. After the annealing, the core is again opened at the cutting region of the laminated plate, a U-shaped structural member 55 is formed, coils 59 and 61 are fitted in the leg parts 57 of the member 55 and after that, the core is again closed. Before this reclosing, a misalignment of the fellow adjacent groups is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a transformer, typically a distribution transformer, and particularly to a transformer whose iron core is made of a laminated plate of thin amorphous metal. Typically the laminate thickness is about 0.00254 co+ (0.001 in).
This invention is disclosed in detail as an example in which the invention is applied to a transformer having an iron core wound with an amorphous metal web. In this respect the invention has great advantages and it will be understood that the principles of the invention can also be applied to pond type transformers within the scope of the equivalents of this application. Westinghouse Electric Corporation
Milan D. Valencic and Deninis A. Schaffer were transferred to OrpraLion.
U.S. Pat. No. 4,709,471 to John Buffer discloses a method for manufacturing the cores of these transformers. U.S. Pat. No. 4,761,630 by Frank H. Grimes and Eugenius Hammack, assigned to Westinghouse Electric Corporation, discloses that these iron cores Structural features are disclosed. The Valencik patent teaches that a web of amorphous metal is wound into a closed helical core ring, ie, a core structure with a window in the center. The spiral turn is the M of the iron core
It forms an R plate. The laminates forming the closed core structure are then cut into successive stepped groups. The closed structure is then opened and transformed into a U-shaped structure, the arms of which are fitted with transformer coils.

The arms of the U-shaped structure are then abutted and the U-shaped structure is transformed back into a closed structure. The Grimes patent discloses a core having a polymerized step as taught by the Valencik patent.

In explaining this invention, it is desirable to briefly explain the Grimes patent in order for those skilled in the art to understand this invention. Figures 3 and 4 of the Grimes patent show an enlarged partial view of the core in a direction perpendicular to the edges of the laminates. If Figure 3 were enlarged to show the entire core, the laminates would be shown in a raceway or toroidal shape.
The structure shown is stepped with steps overlapping their adjacent laminates. In this application, each unit A, B, or C or D, E, or F of the laminate is referred to as a step, or the combination of steps A, B, and C, or the combination of steps D, E, and F. is called a group. The laminate typically has a thickness of 0.00
254cm (0.OO1in) I, so the thickness of step F is 0.178cm (0.007in)
). Group I) Thickness of EF is 0.053cm
(0.021in). It is said in the Grimes patent that there are 30 laminates in each step. In this case, the thickness of each group is 0.782 cm (0.09 in).
Each step may be less than 7 laminates. In fact, each step may be a single laminate.

Although the Valensic and Grimes patents made significant contributions to transformer technology, a problem was encountered in assembling the core as taught by the Valensic and Grimes patents. During reassembly of the core after the coils have been fitted into the arms of the core, the cut end of the laminate on one side of a group is joined to the end of the same laminate on the opposite side of the group during reassembly. Difficulties arose in aligning the separate ends of the group laminates so that the The small thickness of the group is a major factor causing this problem. In past implementations, one group of laminates was sometimes misaligned with two opposing groups during reassembly. The error is obvious when the reassembly of the joint is completed, leaving an extra group of laminates with a comparison group for the joint. For example, according to FIG. 3 of the Grimes patent, the right 21 laminate of group ABC is joined to the left laminate of group DEF instead of being joined to the left fine laminate of group ABC.

When this happens, the completed core will have the laminates unbonded and the core will have to be reassembled. This defect cannot be discovered until the core is completed. Moreover, after the above-mentioned error has occurred, an error also occurs on the opposite side during subsequent reassembly. That is, the left laminate of a group like DEF is ABC.
The right laminate of the group is abutted like this. At this point, the error has been corrected and the iron core has been completed, so no error is found in the tomb, but the performance is degraded.

Other problems arise with cores where there is a breakable joint in the yoke or one of the legs.

This problem is based on the principle that the partial net cross-sectional reduction resulting from the voids forming the joints in the core is one of the many factors that determine the output of the excitation pool in the transformer. This is an essentially fundamental problem. The net cross-sectional area is reduced and the required excitation power is increased by the air gap in the ff plate of the joint. This problem is particularly important in cores formed from amorphous metal laminates, since in use such cores operate at dielectric near saturation. A slight reduction in the net cross-sectional area of the core results in dielectric smoothing when the core is operated. In joints containing multiple voids, especially if the voids are stacked, the net cross-sectional area is essentially reduced - adversely affecting the dielectric loss of the core at TRI electrical saturation.

Other problems that arise when the rammed, single-stepped core taught by the Grimes patent is reassembled are:
Because of the tendency of laminates to stick to each other, one or more groups of cutting steps can be misaligned and misplaced relative to the opposite group. This error is also only discovered after the joint has been completely reassembled. This error occurs on the side of the contact h of the longest laminate located at the top, assuming the joint is reassembled in a horizontal position. Shorter laminates in adjacent groups tend to adhere.

The opposite side of the core, with the longest laminate at the bottom, is self-separated within the group.

The aim of the invention is to overcome the above-mentioned drawbacks and deficiencies and to provide a method for achieving this aim.

That is, the object of the present invention is to have an amorphous metal core formed by a number of spirally wound turns, ie, a number of thin laminates, which core is made of an amorphous metal to enable the insertion of a coil. A method of manufacturing a transformer which is opened and then reclosed by abutting the ends of the cut laminates, in which case the error of the laminates being abutted during re-interval will be eliminated. The goal is to provide the following. It is also an object of the present invention to increase the cross-sectional area of a heavy laminate having voids created by cutting the laminate.
The objective is to provide a method for manufacturing transformers. According to this invention, the joint is formed by cutting the laminate, and the cutting angle is not perpendicular to the longitudinal center line of the laminate, or perpendicular to the plane of the laminate. The purpose is to provide iron cores that differ somewhat by 90 degrees and are thus easily equated because the cut ends of the same lamella board are at the same angle to the centerline. especially,
The laminates forming the core are subdivided into stacked groups.

Every other group is cut at an angle, i.e. the cut is cut at an angle and not perpendicular to the center line, but in one direction, and the groups between the groups are cut at an angle in the opposite direction. ie the cuts are cut at an opposite angle to the center line compared to the cuts of every other group. The deviation from vertical is the same in each direction. However, a joint core in which the cuts of every other group of laminates are formed at different angles to the center line is within the scope of the present invention. In fact, the cuts in the laminates of every other or every group may be at right angles to the center line, and the cuts in the laminates of other groups may be oblique. The cut sections of the steps in each group have the same inclination angle. The laminates are cut and the core processed to produce the transformer disclosed by the Barendic patent.
To make the basic cut, the cutter 66 shown in FIG. 6 of Barencik is set with blades 7 and 78 at an appropriate angle to the longitudinal centerline of the laminate. For the purposes of this application, the angle of inclination will be determined as the exact cutting angle relative to the longitudinal centerline. It is desirable that the cutting angle be slightly deviated from perpendicular to the center line. That is, it is desirable that the angle of inclination is large with respect to the center line. In practice, a deviation angle of about 3°, or about 87
It was found that an angle of inclination of ° is satisfied. Attempting angles that deviate significantly from the vertical complicate cutter adjustment and tend to damage the fragile laminate.

It has been found that alignment of the edges of the laminate is best achieved when the cuts are angled in opposite directions by about 87 degrees. It is understood that when this application is practiced at an angle that differs essentially from 87°, it is of equal scope to this application and the published patent. In the practice of the invention, misalignment of the edges of several laminates of adjacent groups is eliminated by the opposite slopes of the groups. The invention also improves upon the mechanization of joint reclosing by effectively separating successive groups at the joint. By first cutting one group in one angular direction, then changing the angular direction of the next group, and repeating this process throughout the core, a herringbone pattern is created in the wound core. That is, by X-raying a joint cut perpendicular to the surfaces of the webs forming the laminate, herringbone or staggered welds will become apparent.

When the core is opened to fit the coils, the opened sheets are separated into opposite cutting groups and it is impossible for the odd and even groups to be located together again. As a result, assembly problems that occurred in the past have been eliminated. If a double error occurs, the junction will appear to be closed correctly, but the measured dielectric loss will be greatly increased. Also, this error is removed.

General T of this The illustrations shown in FIGS. 1 to 9 include a support plate 21 on which an iron core 23 is disposed. The core 23 is made of a thin-walled amorphous metal web 25 wrapped in a toroidal spiral as taught by the Valencic patent. When this web is disposed on the support plate 21 with the axis of the web horizontal, the web having the shape shown in FIGS. 1 to 6 is substantially as shown in FIG. 8.

The turns of the web are the laminated plates 27 (Fig. 9) of the iron core 23. In an embodiment of the invention, the f* plies 27 of the core 23 are subdivided into groups 29, 29a (FIG. 9), each group being a step 31, as disclosed by the Grimes patent. It is subdivided into The steps of each group are as shown in Figure 9.
3 at a constant distance along the longitudinal direction. Figure 9 shows groups of 29.29 m sequentially along the depth of the core. When the axis of the web is horizontal and placed on the support plate 21, group Z9 is at the top of the group, and group 29 is the second group from the top.
There is a. In FIG. 9, the steps in the top group 29 are labeled A, B, C, D and E, and the steps in group 29a are labeled F, G, H, I and J. In the actual implementation of this invention, there are many groups 2929a.

As shown in FIGS. 1 and 2, the apparatus for carrying out the method of the invention includes a cutter 33 having blades 35,36. The cutter 33 is the same as that disclosed by the Valencik patent. The cutter cuts a predetermined number of laminates or stacks 37 at right angles and is positioned and operated to "cut" the laminate.

However, the blades 35,36 are not positioned to make cuts in the laminate at an angle perpendicular to the longitudinal centerline 41 of the web, but are positioned at an angle X to the centerline. be done. The center line is shown here for convenience of explanation. The blades 35,36 are positioned at an angle X with respect to a plane perpendicular to the surface of the web or, as shown, with respect to a straight and parallel edge of the web. In particular, the number of laminated plates in the overlapped portion 37 is set at step 3.
1 (Figure 9). The laminates making up each step are lifted by magnets (not shown) for slicing as disclosed in the Valencik patent. The invention may be practiced with cutters other than those shown by the Valencik patent.

In practicing the invention, the cutter 33 is positioned with its blade inclined at an angle (Fig. 4). After each step is cut by the cutter, the cut stack of laminates is removed on each side by magnets or other means and folded onto the adjacent ends of the core 23. The cutter then tilts its blade 35,36 at an angle
Either the support plate 21 is advanced to the right as shown in the Figures and FIG. 3, or the support plate 21 is advanced to the left. Then, the next step is to lift it by magnets or other methods,
It is cut and the cut portion is removed and folded back. This operation continues until all steps A, B, C, D, E of the top group have been cut. The cut edges 42, 44 of the laminate of each step are shown in FIG. Their end faces are inclined at an angle X with respect to the center line 41.

In FIGS. 5 and 6, the core 23 is folded over with the cut portions 43.45 of the group 29 away from the ends of the core. The cutter 33 is positioned so that its blades 35 and 36 are inclined at an angle Y (FIG. 2) with respect to the center line 41. The slope at angle Y is equal in value and opposite in direction to the slope at angle X.

Steps F, G, H, r, and J are then cut and the cut parts are folded back in sequence.

FIG. 6 shows the cut end surface 4 of step F to step J.
7,49 are shown. Their end faces are inclined at an angle Y with respect to the center line 41.

The angle of inclination to the centerline is typically as large as 87°;
It is emphasized that it is desirable that angles X and Y be equal in value and opposite in direction. The difference in the inclination angles of the cutting parts of the groups that are cut one after another is twice the inclination angle of each group. As a result, mismatches are easily recognized.

The cutter 33 is repositioned with its blades 35, 36 at an angle X relative to the centerline 41 and the third group of steps 31 is cut from the top group. Thereafter, the cutter 33 is again repositioned with its blades 35, 36 at an angle Y with respect to the center line and the steps of the fourth group are cut from the top group. The odd-numbered groups from the R upper group are cut with the blade 35.38 placed at an angle X to the center line, and the even-numbered groups are cut with the blade 35.3
8 is placed and cut at an angle Y with respect to the center line.

This cut is made completely deep into the cutting area of the core.

The cutter blade is preferably positioned so that the cut is made almost symmetrically and at a constant distance with respect to the intersection centerline 51 of the upper part 53 of the core, so that the length of the portion of the core 23 on each side of the cutting area is The sizes are almost equal. Once the core 23 is cut, the cut plane of the core is opened and as taught by FIGS. 10-15 and 17-22 of the Valencik patent (U.S. Pat. The core structure is specially treated to ensure that The invention is not limited to the processing taught by the Valencic patent, but also to the replacement of the Valencic patent by completely different teachings, as well as starting from the teachings of the Valencic patent, i.e. in the processing of the modified core structure 23. It will be understood that the invention may be practiced without affecting the scope of the invention. During processing, the joints of the cut core 23 are opened and closed again. The core is first opened by mechanical handling, then the core is transformed into the desired shape for stress relief treatment by annealing and closed. After annealing,
The core is opened again in the cutting area to form the U-shaped structural member 55, the coil 5961 is fitted into its foot 57, and then the core is closed again. During re-closing of the core, if the axis of the core is horizontal, from the lowest group to the highest group, at the junctions between adjacent steps, the cut end face 42 and the cut end face 44 (FIG. 4) The cut end surface 47 and the cut end surface 49 are brought into contact with each other in an overlapping manner.

During processing, the core is exposed to the feet 57 as shown in FIG.
It is converted into a self-supporting structural member 55 having a. This foot part 57
is free-standing, but the ends of the core forming the joint at the cutting region 63 move from the open position to the closed position as shown in FIG.

It is particularly essential that during the resting period after the coil has been fitted into the foot, misalignment of adjacent groups is prevented, as shown in FIGS. 7 and 8. The invention may be carried out and accomplished as described. FIG. 7 shows the reclosing of the laminates of group 29 consisting of steps A, B, C, D and E (FIG. 9). The fully sloped lines indicating the end faces 42, 44 are in step A,
The end faces of B, C, D, and E are shown, and the end faces of a single laminate are not shown. The steps are folded consecutively from E to A. It is understood that the end face 42 of each step is abutted and aligned with the end face 44 of the same step.
Figure 8 shows the group 1 adjacent to the group shown in Figure 7.
29a, whose gnolep step is F
, G, H, I, J. In this case, the cuts are inclined in the opposite direction to the group cuts of FIG. In this case, the end faces 47 of the steps J to F are in contact with the end face 49 and are in line.

If the left hand end of group 29 shown in FIG.
When abutting the right-hand end of group 29a as shown, end face 49 will be slanted as shown by dash-dotted line 71 in FIG. 7, and misalignment will be readily apparent.

Traditionally, during reassembly, the cut laminates on one side of the two groups are abutted so that the outer edge of the two adhering groups on one side is connected to the edge of the group on the other side. They were faced with a major problem: they tend to be joined together. In the practice of this invention, joining two groups into one group is prevented.

This benefit can be understood from Figure 118. Figure 118 shows three groups 95, 97, 99 connected during the rest period.
The ends 91 and 93 are shown. Each group consists of five steps, each step represented by a line. Group 95 is on the top and group 99 is on the bottom. The cuts in group 97 are angled in the opposite direction to the cuts in groups 95.99. It was found that if the core is located horizontally with its axis, adhesion occurs when the longest web is on top. Assume that the laminates in groups 95.97 at end 91 adhere, but the laminates in group 95.97 at end 93 do not adhere. Then, the group 95 of the end 93 is added to the group 97 of the end 91.
It was decided to join the Since the cuts in group 97 are inclined in the opposite direction to the cuts in group 95,
Misjoining of the ends of group 95 and group 97 will be prevented. The advantage of the present invention in terms of reducing magnetic flux crowding is illustrated in FIGS. 12 and 13. FIG. 12 corresponds to a core in which cuts 42a-42b are perpendicular to a longitudinally extending centerline, as taught in the prior art. FIG. 13 shows center line 4 according to the invention.
1 is a diagram corresponding to an iron core in which cut portions 42-44 are inclined with respect to FIG. In this discussion, the laminates or groups of laminates Rl, R2, Rl', R2- are in the core of the operated transformer.

In each figure, between adjacent steps, e.g. group 2
The transition laminates Rl, R2, Rl', R2' at the junction between step E and step D of 9 are shown.

The magnetic flux fl, f2 is the laminated plate Rl, R shown in FIG.
It is shown as flowing from Ll, L2 through Rl, R2 through No. 2.

The magnetic fluxes H' and f2' are applied to the laminated plates Rl' and Rl' shown in FIG.
It is shown flowing from Ll', L2' to Rl', R2' through R2'. That is, from left to right in both cases.

The transition laminate in Figures 12 and 13 is the one in Figure 9 upside down. To facilitate understanding of this invention, assume that the width of the cut section is 0.635 cIll (0.25 in) and the overlap section is 0.956 c+a (0.375 in). Also assume that the slope shown in FIG. 13 is 60'' with respect to the centerline.

With respect to FIG. 12, magnetic flux f1 flows through L1 until it reaches air gap G1, where it flows inside and through R2. Thereafter, when it passes through the gap C1, it returns to R1.

The magnetic flux f2 flows through L2 until it reaches the air gap C2, where it flows inside and through R1. After that, the air gap G2
When you pass through, return to R2. When magnetic flux flows through a normal path, concentration of magnetic flux occurs in the region L1 in the gap G2 and in the region R2 in the gap G1. One way to minimize this magnetic flux crowding, resultant saturation, and core loss is to widen the magnetic flux crowding by making the surface apex as large as possible. As shown in FIG. 12, in the prior art, the dense magnetic flux is α. 452c+o2 (1 in
Once the magnetic flux f2 passes through the air gap G2, it enters R2 again before reaching the air gap G1. The re-entry of this magnetic flux f2 is 0.953 cm (0.375 cm).
in). Its area is 9.742
cm2 (15 in 2・0.375×4).
This dense magnetic flux is reduced by increasing the overlap. For example, when the size of the heavy part is 1.27 cm (0.5 in), its area is f2.90 cm2 (2 in.
”). However, since increasing the weight means decreasing the number of steps, there is a limit to the surface area in which the transition is located. In the practice of this invention, the magnetic flux [2' is In the air gap G2', it flows from the laminated plate L2' to the laminated plate L2', and after passing through the air gap G2', it enters the laminated plate R2' again.The magnetic flux [1' reaches the air gap Gl' and flows into the laminated plate R2'. After passing through the air gap 61', the magnetic flux H'' reenters the laminated plate Rl'. In the practice of the invention, the slope of the cut relative to centerline 41 is 60°. The surface area of the above gap G2' is 7.419c+
+12 (1.

15 in 2・0.25×4.6). magnetic flux f
The surface roughness of the overlapping part where 2' rejoins the laminate R2' is 11.1
6 cm2 (1.73 in" 0.375 x 4.6). The area increases in each case without reducing the number of steps within that area. The smaller the slope of the cut with respect to the centerline , the area becomes larger and the dense magnetic flux spreads.

Although preferred embodiments of this invention have been disclosed in this specification,
Many variations of that pond are possible. This invention is not limited except to the extent required by the spirit of the prior art.

[Brief explanation of the drawing]

FIG. 1 is a schematic isometric drawing showing an apparatus for carrying out the invention by making a cut section inclined in a certain direction with respect to the longitudinal center line of the laminate; The figure is the first
3 is a schematic side view of the apparatus shown in FIG. 1, showing the making of cuts inclined opposite to the longitudinal centerline; FIG. 3 is a schematic side view of the apparatus shown in FIG. 1; The fourth section shows how a series of cuts is made in a group of steps.
The figure is a plan view seen from the fV-■ line direction in Figure 3, and Figure 5 is the same side view as Figure 3, showing the cut section of a series of steps in the inner group just below the outer group. FIG. 6 shows the method implemented in this invention, and FIG.
A plan view taken in the direction of the Vl line, Figure 7 is a cutaway schematic diagram using isometric method, showing how the core is reassembled with an inclination that is a group laminate cut, and Figure 8 is a Same cutout diagram as Figure 7, group laminate cutout ft
It shows how the core is reassembled with the opposite inclination at the Jr section, Figure 9 is an enlarged cutaway side view looking towards the end of the laminate, showing the reassembled joint, and Figure 10 is FIG. 11 is a side view of a U-shaped core formed in the practice of the invention to receive a coil; FIG. 11 is a side view of a transformer made in accordance with the invention; FIG. Figure 12 is an isometric view showing the path of magnetic flux that changes direction at the joints between steps in a prior art core; The figure is the same enlarged view as Figure 12 and shows the path of magnetic flux in the iron core according to the present invention. In the figure, 23 is an iron core, 25 is a web, 29. ``Z9a is the group, 31 is the step, 42.44 is the cutting part, 59
．． 61 is a coil. 141-

Claims (1)

Claims: 1) having a butt-overlap-stepped transformer core joint, said transformer core joint being generally cut at an angle from a continuous helically wound web; a cut laminate having a number of angled cuts, said cut laminate being rejoined at the ends of the cut laminate by a butted joint after the coil means has been fitted onto said core, and said cut laminate being rejoined at the ends of said cut laminate by a butted joint; The laminates are divided into a number of groups, each group comprising a predetermined number of laminates, and the slanted cuts are butted during reassembly of the core after the coil means has been fitted onto the core. A transformer core that prevents misalignment of the laminate ends and lengthens adjacent flux paths at the abutted joints. 2) Generally formed by stacking groups of laminates one after another in a spiral shape, the slanted cuts of every other group of laminates being at a predetermined inclination with respect to the longitudinal centerline of said laminates. 2. A transformer core according to claim 1, wherein the slanted cuts of the groups between every other group are slanted at an opposite slope with respect to the centerline of the laminate. 3) A transformer core according to claim 1, wherein each group of laminates is subdivided into steps, and the inclined cuts in the laminates of each group consist of a plurality of stepped cuts with the same slope. 4) Generally formed by stacking successive groups of laminates in a helical configuration, with at least every other group or between every other group having sloped cuts relative to the centerline of the web. A transformer core according to claim 1, which is inclined at an angle somewhat different from 90°. 5) Each group of laminates is subdivided into steps, and the slanted cuts in the laminates of each every other group consist of a number of stepped cuts at a predetermined slope, and 3. The transformer core according to claim 2, wherein the inclined cuts in each group of laminates in between are comprised of a plurality of stepped cuts with an inclination opposite to the predetermined inclination. 6) A claim in which the slope angles of the sloped cuts in every other group and the groups in between are essentially equal in value, opposite in direction, and deviate by a small value from 90° with respect to the centerline. The transformer core described in item 2. 7) comprising an iron core inlaid with coil means, said core comprising a number of laminated plates of thin-walled amorphous metal generally wound in a spiral, and defining a closed curve structure with internal windows; said coil means; is wound as a unitary structure surrounding the core, the core having a butt-butt which allows the core to be opened and the coil means to be fitted therein, and the core to be reclosed after the coil means has been fitted to the core. a lap-to-stepped joint; said butt-to-lap-to-step joint is formed by successively cutting groups of laminates in a sequentially stepped relationship; each group having said core; comprising a predetermined number of said laminates for opening and for reclosing said core after said coil means have been fitted into the core, butting the ends of said cut laminates of each group; said cut is inclined at a first predetermined angle somewhat different from 90° with respect to the longitudinal centerline of said laminate in every other group of laminates; a second predetermined angle slightly different from 90° relative to the longitudinal centerline of the group in between; 8) Each group of every other group and the groups in between are subdivided into a number of steps, and the cuts in the laminates of each group become stepped cuts in the laminates of the steps of each group, and each of stepped cuts in groups,
8. A transformer according to claim 7, wherein the angles and inclinations of the laminates relative to the centerline are the same. 9) A claim in which the angles of inclination of the inclined cuts in every other group and the groups in between are essentially equal in value, opposite in direction, and deviate by a small value from 90° with respect to the center line. The transformer according to item 7. 10) A coil means comprising an iron core and a coil means having an integral coil structure wound with turns and having an opening therein for fitting into the iron core, the iron core being formed from a thin web of magnetic amorphous metal. A method of manufacturing a transformer comprising: (a) wrapping said web into a generally helical core structure having a number of stacked laminates around a window; subdividing into groups, said groups being stacked to form said core structure; (c) making a first cut through every other group of laminates in said core structure; each said cut in every other group of laminates is inclined in a direction at an angle somewhat different from 90° to the centerline of said web; (d) every other cut along said core structure; a second cut is made in each of the laminates of the intervening groups along the core structure, and each of the second cuts in the laminates of the intervening group along the core structure is in the center of the web. 9 against the line
(e) separating the laminates at the cut and changing the core structure into a generally U-shaped structure;
(f) an arm of the U-shaped structure terminates in the cut;
(g) Guided by the difference in inclination of the cut ends of the laminates, only one end of the laminates of each group is cut at this end; The ends of the laminates of one group are rejoined by effectively butting only the other end of the laminates of the same group from which the section was cut, so that the ends of the laminates of one group are connected to the ends of the laminates of the adjacent group. A method of manufacturing a transformer comprising preventing bonding to an end of a laminate. 11) A claim in which the angles of inclination of the first cut and the second cut are essentially equal in value, opposite in direction, and deviate by a small value from 90° with respect to the centerline of the web. A method for manufacturing a transformer according to item 10. 12) A transformer comprising an iron core and a coil means having turns wound into a monolithic coil structure having an opening therein for fitting into the iron core, said iron core being formed from a thin-walled web of magnetic amorphous metal. A method of manufacturing a vessel comprising: (a) winding said web into a generally helical core structure having a number of stacked laminates around a window; and (b) forming said core structure into groups of laminates. subdividing, said groups being stacked to form said core structure; (c) making a first cut with every other group of laminates in said core structure; each said cut in a group of laminates is tilted in a direction at an angle somewhat different from 90° to the centerline of said web; (d) between every other group along said core structure; making a second cut through each laminate of the group in;
each of the second cuts is at a different angle to the longitudinal centerline of the web passing through the first cut; (e) separating the laminates at the cuts; and converting the core structure into a generally U-shaped structure, the arms of the U-shaped structure terminating in the cut, (f) fitting the coil structure into the arms of the U-shaped structure, and (g) the first guided by the difference in the angle of the cutting part and the second cutting part with respect to the longitudinal center of the web, and for each group only one end of the laminate of each group is cut in the same group from which this end was cut. rejoining the ends of the laminates of said group by substantially butting only the other ends of the laminates of said group, and joining the ends of the laminates of one group to the ends of the laminates of an adjacent group; A method of manufacturing a transformer including preventing 13) subdividing each group into steps longitudinally displaced from each other along the web and making a first cut and a second cut, said first cut and second cut; is a cut at said step of each group longitudinally displaced along said web, but with respect to the longitudinal centerline of the web between every other group; 13. A method as claimed in claim 12, wherein the groups are at an angle, and the groups between every other group are at a second angle to the longitudinal centerline of the web. 14) A method of manufacturing a transformer with reduced dielectric losses, comprising: (a) winding a web of magnetic amorphous metal into a helical structure with a central window; (b) subdividing the turns of the helical structure into groups; each group is further divided into steps; (c) the steps of each group make a series of cuts in the region of said helical structure, the cuts by the steps of each group being constant longitudinally along said web in a predetermined direction; The cutting part at each step of one group and the cutting part of the following step are spaced apart from each other so that the last turn of the step of the group and the first turn of the subsequent step of the group overlap. , so that the magnetic flux passing through the last turn and through the first turn is guided together into one and the other of the last turn and the first turn in the region of the cut, creating a concentration of magnetic flux in the region, the cuts are made in all groups of the web, (d
) opening the helical structure at the cut portion; (e) then converting the helical structure into a U-shaped structure; (f) fitting a coil into the arm of the U-shaped structure; (g) opening the helical structure at the cut portion; A method of manufacturing a transformer for making a transformer with a helical structure in which the group is reclosed in a region and then reclosed as a core, wherein the cut by the step is at an angle of some degree from 90° to the longitudinal centerline. A method for manufacturing a transformer, characterized in that the core is inclined at different angles, thereby increasing the area of the core in the region of said concentration of magnetic flux.