JPH0232510A - Manufacture of wound iron core and device therefor - Google Patents

Abstract

PURPOSE:To perform tearing and breaking of a weak point part without producing harmful broken pieces for manufacturing a wound iron core by bending a weak point part of a magnetic strip to a direction opposite to the bending direction at the time of winding the strip before it is wound up. CONSTITUTION:A magnetic substance 1 has to form a weak point part 4 at every prescribed position in that taking-up direction while a position of the length, in which a fixed slided amount is added to one rotation portion of a winding axis 5, is specified as a prescribed position and when a running amount of a taking-up belt 13 up to there is measured, the belt 13 is stopped. After the belt 13 is stopped, the upper blade 2 is made to lower to form a stepped half-cut weak point part 4 on the magnetic strip 1 by shearing combined with the lower blade 3 for reopening taking-up the magnetic strip 1 in time with upward resetting of the upper blade 2. The weak point part 4 is cut and bent according to the curvature fitting the outer peripheral surface of a take-in roller 14 in the range of 5 to 45 deg. to the plane followed by being bent in the opposite direction in the range 0 to 30 deg. according to the curvature fitting the outer peripheral surface of the winding axis 5. In this way, the breaking of the weak point 4 can be performed without producing harmful broken pieces.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention provides a wound core in which a one-turn cut type wound core is manufactured by forming a weak point in a magnetic band and tearing it after winding. The present invention relates to a manufacturing method and an apparatus for the same.

(Prior art) Traditionally, as a manufacturing method for this kind of wound core, the
There is a device as shown in Japanese Patent No.-6088. That is, as shown in Figure 7, a magnetic band (generally a silicon steel band)
1 is cut into stepped half-cuts at predetermined positions in the winding direction using an upper blade 2 and a lower blade 3 to form weak points 4, and wound around a winding shaft 5, and then the wound magnetic band 1 is removed from the winding shaft 5, formed into a rectangular shape, annealed, and then, as shown in FIG. The company manufactures cut-shaped wound cores.

(Problem to be Solved by the Invention) In the case of the above method, as shown in FIG. 9, the thickness of the magnetic band 1 is to, the maximum thickness of the weak point 4 is tl, and the remaining thickness of the weak point 4 is t2. Then, at t2-to-t1, the thickness t of the magnetic band 1 at the remaining thickness t2 of the weak point 4.

The overall survival rate α is expressed by the following formula.

Here, in order to tear the weak point part 4 by pressure such as pressure by the above-mentioned supporting die 6 and pressing die 7, the weak point part 4 must be
The residual rate α must be as small as possible, especially a value of 10% or less.

However, if the survival rate α of the weak point portion 4 is reduced in this way, the magnetic band 1 may break during winding, making winding impossible.

Therefore, the survival rate α of the weak point 4 is actually 20[51
We are trying to secure the above value.

However, if a large survival rate α of the weak point 4 is ensured, the above-mentioned suppression cannot reliably tear the weak point 4, and especially if the weak point 4 is broken as shown in FIG. This often causes problems such as deformation but not tearing.

Therefore, as shown in FIG.
A method has been devised in which a wedge 10 is driven in between to apply a tensile force to the weak point 4 and cause it to tear.

According to this method, the force applied to the weak point 4 is greater than that of the pressing method, and therefore the weak point 4 can be torn more reliably than the pressing method.

However, when this method is used, although it can be torn, burrs 11 and fragments 12 are likely to be generated at the torn part as shown in FIG. When assembled, the problem is that it separates from the iron core and enters between the winding layers of the coil, causing dielectric breakdown.

The present invention has been made in view of the above-mentioned circumstances, and therefore, its purpose is to prevent the tearing of weak points after winding up a magnetic band.
To provide a method for manufacturing a wound core that can be carried out in a very convenient manner without producing harmful fragments.

[Structure of the Invention] (Means for Solving the Problem) The method for manufacturing a wound core of the present invention includes forming a weak point at each predetermined position in the winding direction and tearing the core from the weak point after winding. Accordingly, the method for manufacturing a one-turn cut type wound core is characterized in that, before winding the magnetic band, the weak point is bent in a direction opposite to the bending direction during winding.

The wound core manufacturing apparatus of the present invention includes a weak point forming mechanism that forms a weak point at each predetermined position in the winding direction of a magnetic strip, a winding shaft for winding the magnetic strip in which the weak point has been formed, and a winding shaft for winding the magnetic strip in which the weak point has been formed. The present invention is characterized in that it is comprised of a drive mechanism that drives the magnetic band, and a roll that is arranged close to the winding shaft and that bends the weak point of the magnetic band in a direction opposite to the bending direction during winding.

(Function) According to the above means, the weak point of the magnetic band is weakened before winding. Therefore, when such a magnetic band is wound up and then torn from its weak point, the magnetic band is torn in an orderly manner from the weakened weak point.
It does not generate fragments like the conventional method.

In addition, the roll that bends the weak point of the magnetic band in the opposite direction to the bending direction during winding is placed close to the winding shaft.
Even if the weak point of the magnetic band breaks immediately after bending, it can still be wound around the winding shaft.

(Embodiment) An embodiment embodying the present invention will be described below with reference to FIGS. 1 to 6.

First, in FIG. 1, 1 is a magnetic band (generally a silicon steel band), and a stepped half-cut weak point 4 is formed by an upper blade 2 and a lower blade 3 that constitute a weak point forming mechanism. It looks like this. Magnetic band 1 after forming this weak point 4
is wound around a winding shaft 5 driven by an endless winding belt 13. A winding roll 14 that elastically contacts the winding shaft 5 and is movable in the radial direction of the winding shaft 5 is provided between the winding shaft 5 and the new weak point forming mechanism consisting of the upper blade 2 and the lower blade 3. It is being This winding roll 14 guides the winding belt 13 sent through the first idle roll 15 provided above to the outer periphery of the winding shaft 5, and also has a space between the winding belt 13 and the winding shaft 5. Feed the magnetic band 1. After the winding belt 13 is wound around the outer periphery of the winding shaft 5, the winding belt 13 passes through a second guide roll 16 provided below the winding roll 14 in elastic contact with the winding shaft 5, and then passes through a second guide roll 16 provided below the winding roll 14. Third guide roll 17
, and then travels back to the guide roll 15 again via the fourth guide roll 18 provided below. During this running, the driven sprocket 19, which is provided integrally with the third guide roll 17, passes through the chain 20 to the drive sprocket 2.
1, and this driving sprocket 21 is connected to a motor 22.
This is done by being connected to and rotationally driven.

In addition, 23 is a belt running amount measuring device.

Now, in the case of the device configured as described above, when winding up the magnetic band 1, first pull out the magnetic band 1, pass the tip end between the upper blade 2 and the lower blade 3, and then roll the winding roll 14.
Insert between the winding belt 13 and the winding shaft 5 from the lower side on the left side in the figure. Next, by energizing the motor 22,
Activate it. Then, the rotational force is transmitted from the driving sprocket 21 to the driven sprocket 19 via the chain 20, and the third guide roll 17 is rotated integrally with the driven sprocket 19 in the counterclockwise direction shown by the arrow in the figure. In response, the winding belt 13 is pulled downward and runs, and the winding shaft 5 is rotated counterclockwise. For this reason,
The magnetic band 1 whose tip end is inserted between the winding belt 13 and the winding shaft 5 is pulled in the same direction and wound around the winding shaft 5 while being curved.

Here, the winding Q of the magnetic band 1 (rotation amount of the winding shaft 5) is calculated and determined by measuring the traveling distance of the winding belt 13 using the belt traveling distance measuring device 23. That is, since it is necessary to form a weak point 4 in the magnetic band 1 at each predetermined position in the winding direction, the traveling distance of the winding belt 13 to the predetermined position is measured by the belt travel ffi measuring device 23. When this happens, a signal is immediately issued to stop the rotation of the motor 22 and thus the running of the winding belt 13 (rotation of the winding shaft 5). In particular, in the case of this embodiment, the predetermined position of the magnetic band 1 in the winding direction refers to a position with a length equal to one rotation of the winding shaft 5 plus a predetermined shift mP (see FIG. 5). When the travel distance of the winding belt 13 up to that point is determined to be 1llll, the running of the winding belt 13 by the motor 22 is stopped as described above.

Incidentally, the above shift mP is generally determined by the plate thickness t of the magnetic band 1.
Approximately 10 to 30 times o is suitable.

Then, after the winding belt 13 stops, the upper blade 2 is lowered and a stepped half-cut weak point 4 is formed in the magnetic band 1 by shearing with the lower blade 3. Resume winding of obi 1.

Thereafter, by repeating the above-described operations, the magnetic band 1 is wound up while forming weak points 4 at each predetermined position in the winding direction. Regarding this winding, since there is a predetermined shift amount P regarding the formation of the weak points 4 as described above, the weak points 4 do not overlap but are sequentially shifted stepwise. Also, the difference is the fifth
After winding is performed n times from point 5 to point E shown in the figure, the forming position of the weak point 4 is returned to the same position as the 5 point, and from there, the weak point 4 is further shifted sequentially to form the weak point 4. This is repeated to complete the winding of the magnetic band 1.

Therefore, when the magnetic band 1 is wound up as described above, the weak point 4 occurs when the magnetic band 1 is wound around the winding belt 1, as shown in FIG.
3, the winding belt 13 is bent at an angle of 5 to 45 degrees with respect to the plane as shown in FIG. Then, when the magnetic band 1 is wound around the winding shaft 5 as shown in FIG. According to the curvature of 1, it is bent in the same direction within the range of 0 to 30 degrees with respect to the plane, as shown in FIG. 4(b).

By repeatedly bending as described above, the weak point 4 is weakened and its strength is greatly reduced. Therefore, after winding the magnetic strip 1, the forming and
When annealing is performed and the weak point part 4 of the magnetic band 1 is ruptured using the expansion die 9 and the wedge 10 as shown in FIG. Easily torn. This is clear from Figure 6, which was created based on the inventor's experimental results. That is, when a tensile force is applied to the magnetic band 1 whose survival rate α of the weak point 4 is 30 [%] to tear it from the weak point 4, if the above-mentioned repeated bending is not performed (the same Curve A) in the figure shows approximately 15 to 2
Whereas a tensile force of 0 [kg/l1m2] was required, when the repeated bending was performed at 10 degrees each (curve B in the same figure), the tensile force was approximately 5 to 6 [kg/lll12]. When 1/2 of the tensile force is sufficient and repeated bending is performed at 20 degrees each (curve C in the figure), the tensile force is 1.5 to 2.
A tensile force of 0 [kg/Ryu2], about 1/10, was sufficient to tear the container. As a result, the weak point 4 could be torn in an orderly manner, and the generation of fragments as in the conventional method could be avoided. Therefore, it is possible to solve the problem that the fragments detach from the iron core and enter between the winding layers of the coil during installation into a transformer or the like in a subsequent process, causing dielectric breakdown.

Moreover, in this embodiment, since the insertion roll 14 is arranged close to the winding shaft 5, even if the weak point 4 of the magnetic band 1 is torn immediately after being bent by the insertion roll 14, the insertion roll 14 will not be able to be inserted. Since it is sandwiched and wound between the belt 13 and the winding shaft 5, the magnetic band 1
There is no problem with winding.

Note that the present invention is not limited to the embodiments described above and shown in the drawings, and as one example, the winding roll 14
By replacing it with a magnetic roll, it is possible to wind up the magnetic band 1 through the winding belt 13 but in close contact with the winding roll 14, thereby making it easier to bend the weak point 4. Can be accurate. In addition, the bending of the weak point portion 4 before winding is not limited to the case where the winding roll 13 close to the winding shaft 5 is used, but a guide roller or the like may be provided at a position away from the winding shaft 5. The specific angle and the like are not limited as described above. Further, the magnetic band may also be made of an amorphous material other than the silicon steel band.

In addition, the weak point portion 4 is not limited to a stepped l\-cut shape, but may be formed into any other easily tearable shape by pressing, laser, or the like.

[Effects of the Invention] As is clear from the above description, the method for manufacturing a wound core of the present invention winds up a magnetic strip having a weak point and then tears the weak point to produce a one-turn cut type winding. When manufacturing an iron core, the weak point is bent in the opposite direction to the bending direction during winding before winding the magnetic band. It has the excellent effect of being able to rupture the weak point after it has been removed without producing any harmful fragments, and thereby solving problems such as dielectric breakdown caused by the fragments. be.

In addition, in the iron core manufacturing apparatus of the present invention, the weak point of the magnetic band is bent by a roll placed close to the winding shaft, so even if the weak point of the magnetic band is torn immediately after bending, it will not occur. It has the excellent effect of being able to be wound around a winding shaft.

[Brief explanation of the drawing]

1 to 6 show an embodiment embodying the method of the present invention. FIG. 1 is a longitudinal sectional front view of the entire device for winding a magnetic band, and FIG. 2 is a main part of the device. An enlarged longitudinal cross-sectional view of the part; FIG. 3 is an enlarged longitudinal cross-sectional view of the same part in a different state;
Figure 4(a). (b) is an enlarged vertical cross-sectional view showing the bending angle of the weak point of the magnetic strip, and FIG. 5 is a front view of the entire wound magnetic strip.
FIG. 6 is a diagram showing the relationship between the residual rate of weak points and tensile force. Figures 7 to 12 show the conventional method, with Figure 7 being a longitudinal sectional front view showing the method of winding the magnetic band, and Figure 8 being the method of tearing the wound magnetic band. Fig. 9 is an enlarged longitudinal sectional view of the weak point, Fig. 10 is an enlarged longitudinal sectional view of the loop portion where tearing failed, and Fig. 11 shows tearing of the wound magnetic band. FIG. 12 is a partial perspective view showing another method, and a plan view showing the state after the weak point is torn by the same method. In the drawings, 1 is a magnetic band, 2.3 is a weak point forming mechanism consisting of an upper blade and a lower blade, 4 is a weak point, 5 is a winding shaft, 13 is a winding belt, and 4 is a winding roll.

Claims (2)

[Claims] 1. By forming a weak point at each predetermined position in the winding direction of the magnetic strip and tearing the weak point after winding it up,
A method for manufacturing a one-turn cut wound core, characterized in that, before winding the magnetic band, the weak point is bent in a direction opposite to the bending direction during winding. . 2. a weak point forming mechanism for forming a weak point at each predetermined position in the winding direction of a magnetic strip; a winding shaft for winding the magnetic strip with the weak point formed therein; a drive mechanism for driving the winding shaft; and the winding shaft. A device for producing a wound core, comprising a roll arranged close to the magnetic band and bending the weak point of the magnetic band in a direction opposite to the bending direction during winding.