JPH01206610A - Stepped wound core and cutting of strip thereof - Google Patents

Abstract

PURPOSE:To prevent the generation of binding on the inner surface of a coil bobbin and the impossibility of pressure-welding of the coil bobbin by a method wherein the stopped part to be contacted to the coil bobbin of a wound iron core is formed into a roundish shape. CONSTITUTION:The stepped parts X1-X8 that abut on a coil bobbin 2 are each formed into a roundish shape. Besides, the stepped parts X9-X12 which do not abut on the coil bobbin 2 are also formed each into a roundish shape, but these parts may be formed each into a right angle shape. When the stepped parts X1-X8 are formed each into a roundish shape as above-mentioned, the binding of the inner surface of the coil bobbin 2, especially the abutting part 3, and the impossibility of pressure-welding of the coil bobbin 2 are hardly generated. As a result, the binding on the inner surface of the coil bobbin and the impossibility of pressure-welding of the coil bobbin can be prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a step-wound core having a cross-shaped cross section, a multi-step cross section, etc. for a transformer applied to a cylindrical coil bobbin, and a method for cutting out a strip thereof.

[Conventional technology]

The wound core of a transformer to which a cylindrical coil bobbin is applied is
It has the shape shown in FIGS. 7 and 8, but some have a stepped cross section, for example, a cross or multi-step cross section as shown in FIGS. 9 and 10. That is, the wound core 1.1' shown in FIGS. 9 and 10 is made by preparing in advance a plurality of strips having excellent magnetic properties and having different width directions.
This is obtained by winding it according to the mold. A cylindrical coil bobbin 2, which has been divided into two in advance, is pressed against the winding core 1゜1' at the pressure contact surface 3, and by rotating this coil bobbin 2 with respect to the winding core 1, the coil bobbin 2 is wound. A line (not shown) is applied.

[Problem to be solved by the invention]

However, the wound core 1.1′ shown in FIGS. 9 and 10
In this case, the shape of the stepped part is a right angle, and as a result, when the coil bobbin 2 is pressed and rotated, the inner surface of the coil bobbin 2, especially the pressed part, gets caught, making it impossible to wind the wire. Or, in the worst case, there is a problem that the pressure welding work of the coil bobbin 2 becomes impossible.

Therefore, an object of the present invention is to provide a stepped wound core that can prevent the inner surface of the coil bobbin 2 from getting caught and the coil bobbin 2 being unable to be pressed.

Another object of the present invention is to provide a method for cutting out a band material for a stepped wound core, which has high material usage efficiency and high winding efficiency.

A further object of the present invention is to provide a method for cutting out a band material for a large stepped wound core even when the width of the material is small, such as an amorphous metal material.

[Means to solve the problem]

The means for solving the above-mentioned problems are shown in Figures 1A and 2B.
As shown in the figure. Figure 1A shows a wound core with a cruciform cross section;
FIG. 1B shows a wound core with a multi-stage cross section. In FIG. 1A, the stepped portions indicated by arrows X1 to X8 that abut the coil bobbin are rounded, and in FIG. 1B, the stepped portions indicated by arrows Y1 to YI□ that abut the coil bobbin are rounded. It has a rounded shape.

In addition, in the above-mentioned method for cutting out a strip material for a wound core, both straight edges of the material are left straight during cutting, and when the strip material is cut out and wound into a predetermined shape. By cutting out along one curve so that the convex part and the concave part face each other so that a stepped cross-sectional shape can be obtained, two pieces of wood can be obtained! The strip material for the iron core is obtained continuously, and the portions of this curve corresponding to the steps of the stepped cross-sectional shape are made smooth. In addition, if you use this method of cutting out the strip material,
The stepped portion and the first
The stepped portion indicated by arrows Y13 to Y2° in Figure B also has a rounded shape.

Furthermore, one of the straight edges of the material is left straight, and when the strip material is cut out and wound into a predetermined shape, half of the stepped cross-sectional shape is obtained. By cutting out along the curve, a strip material for one wound core is obtained continuously, and at this time, the part corresponding to the step of the stepped cross-sectional shape in this curve is smoothed, thereby The two obtained wound cores with stepped cross-sections are combined to obtain one stepped wound core.

[For production]

According to the above-mentioned means, since the stepped portion that contacts the coil bobbin has a rounded shape, it is possible to prevent the inner surface of the coil bobbin from being caught and the coil bobbin to be unable to be pressed against the coil bobbin. Further, according to the above-described method for cutting out a strip material for a wound core, the usage efficiency of the material is very high, and since a plurality of strip materials are continuously wound, the winding efficiency is also very high. Furthermore, when the material width is small, such as with amorphous metal materials,
Two wound cores are combined to obtain one wound core, thereby making it possible to manufacture a large-sized wound core.

〔Example〕

FIG. 2 is a sectional view showing a first embodiment of a stepped wound core according to the present invention, and shows a case where the stepped wound core has a cruciform cross-sectional shape. That is, the stepped portions X1 to X8 that come into contact with the coil bobbin 2 have a rounded shape. Note that although the stepped portions X, to X1□ that do not contact the coil bobbin 2 also have a rounded shape, these portions may be at right angles. In this way, the stepped part
By making 1 to X8 rounded, the coil bobbin 2
It is very unlikely that the inner surface of the coil bobbin 2, especially its contact portion 3, will get caught or that the coil bobbin 2 will not be able to be pressed against the coil bobbin 2. It also becomes possible to increase the effective area of the cruciform cross section, thus contributing to the miniaturization of the transformer.

FIG. 3 is a cross-sectional view showing a second embodiment of the stepped wound core according to the present invention, and shows a case where the stepped-wound core has a multi-step cross-sectional shape. That is, the stepped portion Y+-Y+□ that contacts the coil bobbin 2 has a rounded shape. In this case as well, the stepped portions Y13 to Y2o that do not contact the coil bobbin 2 also have a rounded shape, but these portions may be at right angles. In this way, by making the stepped portion Y+ = Y, 2 into a rounded shape, it is almost impossible for the inner surface of the coil bobbin 2, especially the pressure welding portion 3, to be pulled off or for the coil bobbin 2 to be welded to be impossible. .

Furthermore, it is possible to increase the effective area of the multi-stage cross-section, thus contributing to the miniaturization of the transformer.

Note that the gap between the stepped portion and the coil bobbin 2 in FIGS. 2 and 3 can be sufficiently secured as a cooling air or cooling oil duct.

FIG. 4A is a plan view of a material for explaining a method of cutting out the band material for the cross-shaped wound core shown in FIG. 2. FIG.

In FIG. 4A, the edges 41a and 41b on both sides of the raw material 41, which has straight edges, remain straight and are cut out along one predetermined curve 42. This results in two continuous strips l. In this case, one row of uneven portions of the strip 1 corresponds to one row of uneven portions of the strip 1, thereby increasing the utilization efficiency of the material. Each strip 1 is then obtained by cutting at the location 43.

The basic idea of manufacturing the cross-shaped cross section of FIG. 4A is to draw semicircles one on top of the other as shown in the figure, and determine the pattern of the cutout lines 42 so that they touch each other's semicircles. However, in reality, the length direction of the cut out strip material 1 is approximately 5 mm in the width direction.
00 times the dimension, and therefore the semicircle mentioned above is a semi-ellipse in shape.

When the strip material is cut out as shown in FIG. 4A, the usage efficiency of the material 41 is approximately 100%.

The cutting location 43 in the material of Figure 4A is actually the cutting location 43 of the material in Figure 4B.
The result will be as shown in the figure. That is, in actual cutting, the beginning of the roll is short and the part near the end is long, as shown in the figure. This is because the length per winding becomes longer each time it is wound.

Note that if the portion indicated by the arrow 43a is cut out in a straight line, the stepped portions X, -XI□ in FIG. , ~X12 are rounded as shown in FIG.

FIG. 5A is a plan view of a material for explaining a method of cutting out the strip material for the multi-stage cross-section wound core shown in FIG. 3.

In FIG. 5, the edges 41a and 41b on both sides of a material 41, which has straight edges, remain straight and are cut out along one predetermined curve 42. Thereby, two continuous strips 1' are obtained. In this case as well, one row of uneven portions of the strip 1' corresponds to one row of uneven portions of the strip 1', thereby increasing the utilization efficiency of the material. However, the shaded portions are truncated, and therefore the usage efficiency of the material 41 is slightly lowered. Each strip 1' is then obtained by cutting at the location 43'.

The basic idea of manufacturing the multi-stage cross section shown in Fig. 5 is to draw semicircles one on top of the other as shown in the figure, and determine the pattern of the cutting line 42' so that it touches each semicircle (9), but in reality In this case, the length direction of the cut out strip 1' is approximately 500 times as large as the width direction, and therefore the semicircle mentioned above has a semielliptical shape.

When winding up the continuous strip shown in FIG. 4A (FIG. 4B) and FIG. 5, both edges are held so that the winding center line is a straight line.

Note that if the part indicated by the arrow 43'a is cut out in a straight line, the stepped parts YI3 to Y2o in FIG.
If you cut out the part in the shape of a protrusion, you will get the stepped part YI3~ in Figure 3.
Yzo becomes round as shown in FIG.

The cutting of the curves 42 and 42' in FIG. 4A (FIG. 4B) and FIG.
8375, Japanese Unexamined Patent Publication No. 55-132027), it is possible to perform the process continuously without stopping.

In addition, in Fig. 4A (Fig. 4B) and Fig. 5, the material 4
When the width of the material 41 is limited, such as in the case of amorphous metal materials, only one edge of the material 41 is left straight and curved 42 (or 42') as shown in FIGS. 6A and 6B. Cut out along a similar curve and wind it up. As a result, one continuous strip 1 (or 1') is obtained, and these strips 1 (or 1') are divided into IA, IB (
or 1'A, 1'B), as shown in FIG. 6A (or FIG. 6B), it becomes possible to manufacture a large-sized wound core, that is, a large-sized transformer.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to prevent the inner surface of the coil bobbin from being caught and the impossibility of pressure welding, and
Material usage efficiency can be improved, and multiple strips can be wound in succession, so a significant improvement in winding efficiency can be expected. Furthermore, even when the width of the material cannot be made large, such as with amorphous metal materials, it is possible to manufacture a large stepped core.

[Brief explanation of the drawing]

1A and 1B are cross-sectional views of a stepped-wound core showing the basic configuration of the present invention. FIGS. 2 and 3 are cross-sectional views showing an embodiment of a stepped-wound core according to the present invention. FIG. 4A , FIG. 4B is a plan view of the material explaining the method for cutting out the stepped wound core of FIG. 2, FIG. 5 is a plan view of the material explaining the method of cutting out the stepped wound core of FIG. 3, FIG. 6A, Figure 6B is a sectional view showing the transformation example shown in Figures 2 and 3, Figures 7, 8, and 8 are external views of a general wound core, Figure 9,
FIG. 10 is a cross-sectional view of a conventional stepped wound core. 1.1'...Strip material, 41 River material, 42, 4
2'... Cutting curve, 43, 43'... Cutting location.

Claims (3)

[Claims] 1. A stepped wound core to which a cylindrical coil bobbin for winding a winding wire is applied, characterized in that at least a stepped portion of the wound core that contacts the coil bobbin is rounded. 2. When cutting out a strip material for a wound core with a stepped cross-sectional shape, both straight edges of the material are left straight, and when the strip material is cut out and wound into a predetermined shape, the above-mentioned By cutting out along one curve so that the convex part and the concave part facing each other so as to obtain a stepped cross-sectional shape, two strips for the wound core are continuously obtained. A method for cutting out a band material for a stepped wound core in which the portion corresponding to the step in the stepped cross-sectional shape is smoothed. 3. When cutting out a strip for a wound core with a stepped cross-section, one of the straight edges of the material remains straight, and the strip is cut out and wound into a predetermined shape. By cutting out along one curve such that half of the stepped cross-sectional shape is obtained, a strip material for one wound core is continuously obtained. The part corresponding to the step is a method of cutting out the band material for the stepped wound core, which is smoothed.