JPH0878265A - Winding iron core mold holding device - Google Patents

Abstract

PURPOSE: To enable a molded rectangular winding iron core to be kept unchanged in shape till an annealing process is finished by a method wherein an L-shaped metal piece is fastened to each of the outer surfaces of the corners of the molded rectangular winding iron core. CONSTITUTION: A molding piece 13 is inserted into a circular iron core element body to mold it into a rectangular winding iron core B, an L-shaped metal piece 19 is provided and fastened to each of the outer surfaces of the corners of the molded rectangular winding iron core B by a fastening band 20, and the leg and yoke of the winding iron core B are set nearly rectilinear by pressing the L-shaped metal pieces 19 against them, whereby the winding iron core B is kept well in a rectangular shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a forming / holding device for a wound iron core used in a transformer or the like, and its object is an iron core material made of a silicon steel strip or an amorphous magnetic alloy thin strip. When the iron core body wound in a circular shape is formed into a rectangular shape by using, the rectangular state of the wound core is satisfactorily maintained.

[0002]

2. Description of the Related Art Conventionally, wound cores used for transformers, etc., are made by cutting an iron core material such as a silicon steel strip as shown in FIG. Then, the iron core element body 1 having a circular shape is formed by winding the iron core element body 1 into a circular shape, and a pair of outer mold dies 2, 3 for press molding are formed inside the iron core element body 1.
And the inner die 4 (the two-dot chain line in FIG. 8) are inserted with the inner die 4 in the middle, and then the inner die 4 is pressed downward by a pressing press or the like to obtain the outer die. The dies 2 and 3 are pushed and expanded in the vertical direction of FIG.
Form a substantially rectangular iron core equal to ~ 4. When the iron core element 1 is formed into a rectangular shape, the inner die 4 and the pair of outer die 2 and 3 which are in contact with the die 4 are formed so that the portions where both die contact each other are tapered. At the same time, the inner die 4 itself is formed in a wedge shape, and the outer die 2 and 3 are inserted into the core body 1 at intervals as shown in FIG. 4 outer mold 2,3
By press-fitting in between, the circular iron core element body 1 was formed into a rectangular wound iron core 9, as shown in FIG.

Next, as shown in FIG. 9, tightening plates 5 and 6 are applied to the outside of the winding core 9 formed in the rectangular shape, and the tightening plates 5 and 6 are mutually bolted 7, 7a and nut 8. To maintain the winding core 9 in a rectangular shape by tightening,
The strain relief annealing of the wound core 9 is performed. After annealing, the tightening plates 5 and 6 and the mold dies 2 to 4 were removed from the wound core 9 to produce a rectangular wound core 9.

[0004]

When forming the wound iron core 9 into a rectangular shape, the circular iron core body 1 is formed into a rectangular shape using the outer and inner mold dies 2 to 4 and then the shape is maintained. In order to do so, tightening plates 5 and 6 are applied to the outside of the leg iron portion and the yoke portion of the rectangularly shaped winding iron core 9 each time, and these,
Long bolts 7 and 7a having different lengths were passed through the tightening plates 5 and 6 and fastened with a nut 8. That is, as shown in FIG. 9, the tightening plates 5 and 5 are provided on the leg iron side of the winding iron core 9, and the tightening plates 6 and 6 are provided on the yoke part side.
Tightening plates 5, 5, which correspond to each other
6, 6, and the long bolt 7 with the iron core 9 sandwiched between them.
It was fastened individually using 7a. However, in the work of mounting the tightening plates 5 and 6, the tightening plates 5 and 6 are applied to the outer periphery of the winding core 9 as shown in FIG. Because it was fastened individually by
It is very unstable, and more than one bolt 7,7
As a result, all of the steps a are manually tightened, so that it takes time and labor, and since the work is performed by erecting the iron core, there is a problem in safety and the forming work of the wound iron core 9 is efficiently performed. Was difficult.

In order to maintain the rectangular state of the rectangular wound iron core 9, a pair of tightening plates 5 and 6 having different lengths are prepared, or one set of these tightening plates 5 and 6 are provided. At least four bolts 7 and 7a for fixing the coil to the winding iron core 9 are required, and the tightening plates 5 and 6 and the bolts 7 and 7 are required.
Since a requires a different length in advance for each different type of wound core 9, that is, for each different window size,
Coupled with the troublesome installation of the tightening plates 5 and 6,
Not only is it uneconomical to manufacture the wound iron core 9, but also the number of types of the tightening plates 5, 6 and the bolts 7, 7a increases.
Since it takes time to store and manage it, and when using it, it is necessary to carefully install the tightening plates 5 and 6 because different sizes may be used by mistake.

In view of the above-mentioned various problems, the present invention provides one type of molded holding metal fitting for holding a rectangular state of a wound iron core that has been rectangularly shaped, and equips the wound iron core with a simple means. An object of the present invention is to provide a forming / holding device for a wound iron core having a simple structure capable of smoothly holding the rectangular state of the wound iron core.

[0007]

According to the present invention, when a circular iron core element is formed into a rectangular shape, for example, a forming metal piece composed of a corner type metal, a leg and a yoke type plate is used. On the inner peripheral surface of the body, four corner-shaped dies are respectively inserted and arranged at positions where the iron core element can be formed into a rectangular shape, and each of the corner-type dies has a leg iron portion side and a yoke portion side of the iron core element body, respectively. And, a pair of tapered guide grooves are
It is formed with a space of, and these guide grooves
A pair of leg mold plates are press-fitted on the leg iron side, and a pair of yoke mold plates are press-fitted on the yoke part side, and each of the distributed corner molds is radially pushed to form a circular iron core body. A rectangular wound iron core is obtained by forming a rectangular shape.

Formed holding metal fittings for holding the wound core in a rectangular state are attached to the outer peripheral sides of the respective corners of the wound core formed in the rectangular shape. The molded holding metal fitting is formed, for example, by bending a metal material such as a steel plate into an L-shape with its width dimension slightly longer than the width of the winding iron core. Forming a rectangular-shaped wound iron core by applying it to the outer periphery of each corner of the iron core, and forming a molded holding metal that holds these four shaped holding metal fittings with a tightening band to lock and hold the winding iron core. A holding device is configured.

[0009]

According to the present invention, when a circular core element body is formed, for example, four corner type dies are simultaneously pushed by a radiating method using a leg and a yoke type plate to form an iron core element into a rectangular shape. By adopting the forming metal fittings described above, since each corner die rarely makes sliding contact with the inner peripheral surface of the wound core to generate a frictional force, there is almost no processing distortion during rectangular forming of the wound core.

Further, in the case where the rectangular shape of the wound core is held by the molded holding metal fittings after the rectangular iron core body is rectangularly shaped, the metal fitting pieces constituting the shaped holding metal fittings are applied to the outer circumferences of the corner portions of the wound iron core. The rectangular shape of the wound core can be easily maintained simply by tightening with the tightening band to the wound core, and the L-shaped metal fitting piece has a smaller radius of curvature than the radius of curvature of the outer periphery of the corner of the wound core. By setting the pressing force of the metal fitting piece against the winding iron core, a force corresponding to the tightening force of the tightening band by the wedge effect of the metal fitting piece itself acting on the corner portion of the winding iron core is used. Since it can be easily obtained as a force for pressing the (leg iron portion and the yoke portion), the leg iron portion and the yoke portion of the winding core can be held in a substantially straight line state.

Further, since the forming and holding apparatus of the present invention can be attached by utilizing the outer circumference of the corner portion of the wound core,
When the coiled core is annealed, there is no forming metal fittings or metal fittings near the legs and yokes of the coiled core, so the coiled core can be heated to a predetermined temperature in a short time due to economical and efficient use of energy. Since it is possible to heat the core, it is possible to perform the forming and annealing work of the wound core quickly and reliably.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of the molding and holding apparatus of the present invention is shown in FIG.
Through FIG. 6. First, the molding fitting will be described. In FIG. 2, 11 is a core material made of silicon steel strip or amorphous magnetic alloy thin strip, which is continuously wound,
Alternatively, reference numeral 12 denotes an iron core element formed by cutting each winding and winding it in a circular shape, and 12 is a tightening band wound around the iron core element 11. Reference numeral 13 denotes a metal mold for rectangularly molding the circular iron core element 11, and as shown in FIGS. 5 and 6, four bar-shaped corner metal molds 14 and a pair of metal molds interposed between the corner metal molds 14. As shown in FIG. 5, the plate-shaped leg-shaped plate 15 and the yoke-shaped plate 16 are formed by forming a rectangular frame.

Next, the details of the metal mold 13 will be explained. First, as shown in FIG.
A metal rod having a predetermined diameter is cut into a length that is slightly longer than the axial length of the iron core body 11, and the two guide grooves 17 are provided at an interval of 90 ° on the rod. , 17a
Are formed in parallel with each other with a required angle inclination (taper shape), and the leg template 15 is orthogonal to the one guide groove 17 and the yoke template 16 is orthogonal to the other guide groove 17a. It is formed with a width dimension that can be removably fitted.

The leg mold plate 15 and the yoke mold plate 16 fitted into the guide grooves 17 and 17a of the corner mold 14 have lengths substantially the same as those of the corner mold 14. The plate thickness is a tapered guide groove 17,
It is formed in a trapezoidal shape with a width dimension that allows it to be removably fitted in 17a, and with its side edges inclined at the same angle as the tapered portions of the guide grooves 17, 17a.

Next, the molded holding member 18 will be described.
As shown in FIGS. 1 and 4, the forming and holding metal fitting 18 is composed of four metal fitting pieces 19 which are engaged and held on the outer circumferences of the respective corners of the rectangular-shaped wound iron core B. Using the tightening band 20, the corner portion (4
It is attached to the winding core B by being attached to the winding place), and the width dimension of the metal fitting piece 19 is the same as the axial length dimension of the winding core B or is slightly wider. Also, the length dimension is a length dimension that covers the corner portion of the winding core B, and the radius of curvature of the metal plate such as a steel plate is smaller than the radius of curvature of the outer circumference of the corner portion of the winding iron core B. Is formed by bending in an L shape at about 90 °. As shown in FIG. 4, when the metal fitting piece 19 is attached to the corner portion of the wound core B, both ends of the bent portion are the outer peripheral edge of the corner die 14 as shown in FIG. It is formed in an L shape with a length slightly protruding from.

Next, the case of using the molding and holding apparatus of the present invention will be described. First, a case will be described in which the core element body 11 wound in a circular shape is formed into a rectangular shape using the forming metal piece 13. When forming the rectangle, as shown in FIG. 2, four corner molds 14 are provided on the corner mold 14 at positions corresponding to the corners of the circular core body 11.
The guide grooves 17, 17a of the strip are arranged so as to face each other so that a rectangular frame can be formed in the core element body 11. In this case, the corner die 14 has guide grooves 17, 17
The taper groove of a is located in the core element body 11 with the shallow position facing upward. Then, in FIG. 2, the guide grooves 17 and 1 facing each other between the upper and lower portions of the corner die 14 are opposed to each other.
A pair of leg mold plates 15 and 15 are inserted between 7 and the guide grooves 17 of the corner molds 14 facing each other in the left-right direction of FIG.
A pair of yoke type plates 16 and 16 is inserted between a and 17a.

As described above, the required legs and the yoke mold plates 15, 1 are provided in the guide grooves 17, 17a of each corner mold 14.
After inserting 6 pairs one by one, the mold plates 15 and 16 are simultaneously pressed downward by a pressing means (pressing device) (not shown) to be press-fitted between the required corner molds 14 and 14. In each corner die 14 arranged in the core element body 11, the trapezoidal legs and the yoke die plates 15 and 16 have guide grooves 17 and 17.
As it moves downward in a, it is pushed in the direction of the arrow shown in FIG. 2 to expand the circular core element body 11 into a rectangular shape as shown in FIG. 3 to form the wound core B in a rectangular shape. At this time, the corner-shaped metal 14 is pushed in the direction of the arrow in FIG. 2 as the trapezoidal legs and the yoke-shaped plates 15 and 16 descend in the guide grooves 17 and 17a, but the inner circumference of the core element body 11 is reduced. Since the surface hardly slides, a mechanical processing strain is generated in the corner portion of the inner peripheral surface of the wound core B formed into a rectangular shape by the pushing of the corner die 14 due to the rectangular forming of the core element body 11. Can be significantly suppressed.

Next, description will be made on the case where the rectangular shape of the rectangularly shaped wound iron core B is held by the shaping and holding metal fitting 18. Even if the wound iron core B is formed into a rectangular shape by using the forming metal fitting 13, the outer peripheral surfaces of the leg iron portion (leg) and the yoke portion (yoke) are not straight but are often curved. .
In this state, on the outer circumference of each corner of the outer peripheral surface of the wound core B,
As shown in FIGS.
Apply the metal fitting piece 19. As shown in FIG. 4, these metal fitting pieces 19 are formed by bending a metal plate such as a steel plate at an angle close to a right angle, and when applied to the outer periphery of the corner portion of the winding core B, as shown in FIG. Since the radius of curvature is smaller than the radius of curvature of the outer circumference of the corner portion of the wound core B, a space S is formed between the inside of the metal fitting piece 19 and the outer top of the corner portion. Becomes Moreover, FIG.
Since the metal fitting piece 19 is formed such that its width dimension is slightly longer than the axial dimension of the winding core B, the fitting piece 19 is attached in a state of protruding upward from one end surface of the winding core B.

As described above, the metal piece 19 is wound around the iron core B.
After applying to the outer periphery of each of the corners, as shown in FIG. 1, by tightening the tightening band 20 from the outside of each metal fitting piece 19 to attach the metal fitting piece 19 to the winding core B, the winding core B Is held in a rectangular shape by a molded holding metal fitting 18 made of each metal fitting piece 19. And in the present invention,
By disposing the metal fitting pieces 19 on the outer circumferences of the respective corner portions of the winding iron core B and tightening the tightening bands 20 on the outer circumferences of the corner portions of the winding iron core B, the respective metal fitting pieces 19 are free at both ends of the bent portion. At the end, the tightening force of the tightening band 20 can be effectively received and the leg iron portion and the yoke portion of the winding core B can be maintained in a straight state. When the rectangular shape of the winding core B is held,
The reason why the force for linearly pressing the leg iron portion or the like is applied can be obtained by the following calculation formula.

As shown in FIG. 7, the above-mentioned calculation formulas are the force F for pushing the top X of the corner portion of the wound iron core B into the space S of the metal fitting piece 19 by the wedge action, and the above-mentioned pushing force. It can be calculated by obtaining the relationship with the reaction force R acting on the opposite side to the force. Now, for example, when the tightening force of the tightening band 20 is 600 kg and 2α is 90 °, F is 600√2. Then, the reaction force R obtained by the wedge action can be obtained by the following equation.

[0021]

[Equation 1]

Here, 2α = 90 ° (bending angle of the metal fitting piece 19) μ ₀ = 0.8 (coefficient of static friction between the metal fitting piece 19 and the winding core B) is expressed. Then, the value of α of 45 ° and the value of static friction coefficient μ ₀ of 0.8 are

Substituting into the calculation formula shown in the formula (1) of [Formula 1].

[0023]

[Equation 2]

[0024]

The tightening force of the tightening band 20 is calculated by the formula (2) of [Equation 2].
It was found that the reaction force R was about 331 kg with respect to 00 kg. As a result, as shown in FIG.
The reaction force R applied to the portion (edge of the corner portion) is in balance with the force applied to the free end of the metal fitting piece 19 obtained by the tightening force of the tightening band 20. Therefore, the metal piece 1
The force applied to the free end of 9, that is, the Y portion of FIG. 7, is about 3
Since the weight is 31 kg, when the L-shaped metal fitting pieces 19 are arranged at the respective corners of the winding core B and are fastened with the tightening band 20 having a tightening force of 600 kg, each metal fitting piece 19 has its free end side. Since the pressing force of about 331 kg obtained in step 1 can press the portion of the outer periphery of each corner portion of the winding core B that comes into contact with the metal fitting piece 19 toward the corner die 14 side, the leg iron portion of the winding core B and the yoke It is possible to press and urge the portion substantially linearly, and it is possible to satisfactorily maintain the rectangular state of the wound iron core B after rectangular shaping without requiring a particularly large force.

As described above, the radius of curvature of the metal fitting piece 19 for linearly pressing and urging the leg iron portion and the yoke portion of the winding iron core B is as shown in FIG. Since the radius of curvature is smaller than the radius of curvature of, the pressing force obtained at the free end of the metal piece 19 can be easily obtained by the wedge action. As a result, the tightening force of the tightening band 20 can be effectively used. It is possible to maintain the rectangular state of the wound iron core B.

After the rectangular forming work of the wound core B is completed as described above, annealing is performed with the forming and holding metal fittings 18 and the forming metal fitting 13 being provided on the winding iron core B to remove the distortion of the entire winding iron core B. To do. The wound iron core B that has undergone the annealing is first disassembled from the molded holding metal fitting 18 by releasing the tightening of the tightening band 20 and pulling the metal piece 19 away from the corner portion of the winding iron core B, and subsequently, the wound iron core. The mold plates 15 and 16 of the leg and the yoke are extracted from the inside of B from the corner mold 14 and, finally, the corner mold 14 is removed to eliminate the state of forming and holding the wound core B.

In the present invention, the rod-shaped corner metal 14 and the plate-shaped leg and the yoke-shaped plate 1 are used as the metal mold 13.
Although the example using Nos. 5 and 16 has been described, the present invention is not limited to this, and the circular core element body 11 is formed into a rectangular shape by using a conventionally used forming metal member made of a wedge-shaped die for press forming. You may do it. Also, an L-shaped metal fitting piece 1
It is needless to say that 9 may be formed by combining a pair of plate members at a right angle and forming an L shape without bending a steel plate or the like into an L shape.

[0028]

Since the present invention is constructed as described above, it has the following effects. (1) According to the present invention, by applying a metal fitting piece having an L-shaped planar shape on the outer periphery of a corner portion of a rectangularly shaped wound iron core, and integrally fastening the metal piece to the wound iron core with a tightening band, Since I tried to maintain the rectangular state of the winding iron core,
Compared to the conventional method of maintaining the rectangular state of the wound core using a tightening plate and bolts, the rectangular holding operation of the rectangularly formed wound core can be performed quickly, easily, and economically. it can.

(2) The present invention is convenient because, when the rectangular state of the wound iron core is maintained, the molded holding metal fitting can be formed by using the L-shaped metal fitting piece and the tightening band. In addition, since the bending angle of the metal fitting piece is smaller than the angle of the outer circumference of the corner portion of the winding iron core, the tightening force of the tightening band can be effectively used at the corner edge of the winding iron core. It is possible to press the iron core itself from the outside with a constant force. That is, as a result of enabling the wedge action to effectively act on the metal fitting piece, the winding iron core can be held in a rectangular shape without using a special pressing member or pressing means, and at the same time, the leg iron portion and the yoke portion can be further improved. Since the pressing force can be applied in a straight line, the rectangular holding means of the wound iron core can be easily manufactured at low cost.

In addition, since the width of the metal piece corresponding to the axial dimension of the wound core is the same as or longer than the width of the wound core, the force for pressing the wound core acts. However, the wound iron core is not damaged at all, and the wound iron core can be effectively held in a rectangular shape with a uniform force, which is convenient. Moreover, when the metal fitting piece is attached to the outer periphery of the corner portion of the winding iron core, the fastening band can be fastened without raising the winding iron core, so that the work of attaching the molded holding metal fitting can be performed safely.

[Brief description of drawings]

FIG. 1 is a perspective view showing a usage state of a wound core forming / holding device of the present invention.

FIG. 2 is an explanatory view showing a state in which a wound metal core is formed into a rectangular shape by inserting a metal mold into a circular iron core body in the present invention.

FIG. 3 is an explanatory view showing a state in which a wound iron core is formed into a rectangular shape by using a forming fitting.

FIG. 4 is an explanatory view showing a state in which a wound iron core formed in a rectangular shape is held in a rectangular shape by a forming and holding metal fitting.

FIG. 5 is a perspective view showing an embodiment of a molding tool.

FIG. 6 is a perspective view of a corner die that constitutes a part of a molding tool.

FIG. 7 is an explanatory diagram showing a relationship of forces applied to a corner portion of a wound iron core.

FIG. 8 is an explanatory diagram showing a state in which a conventional circular iron core element body is formed into a rectangular shape.

FIG. 9 is an explanatory diagram showing a rectangular holding state of a conventional wound iron core formed into a rectangular shape.

[Explanation of symbols]

 11 Iron Core Element 13 Molded Metal Fitting 14 Corner Mold 15 Leg Mold Plate 16 Yoke Mold Plate 17, 17a Guide Groove 18 Molded Holding Metal Fitting 19 Metal Fitting Piece 20 Tightening Band

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location C21D 9/00 S 9352-4K

Claims (3)

[Claims] 1. A wound core formed by winding an iron core material such as a silicon steel strip in a circular shape into a rectangular shape with a metal fitting and forming the rectangular shaped wound core. L-shaped metal fitting pieces are arranged on the outer periphery of each corner portion of, and the metal fitting pieces are fixed to the winding core by a tightening band so as to be immovable, and the winding core is held in a rectangular shape. A holding device for a wound iron core, comprising: 2. The metal fitting pieces forming the molded holding metal fittings arranged at the respective corners of the wound core are formed such that the width dimension thereof is equal to or slightly longer than the axial length dimension of the wound core. The forming / holding device for a wound iron core according to claim 1. 3. When the metal fitting pieces constituting the molded holding metal fittings arranged at the respective corners of the wound core are formed in an L shape, the radius of curvature thereof is smaller than the radius of curvature of the outer circumference of the corner of the wound core. The apparatus for forming and holding a wound iron core according to claim 1, characterized in that it is bent.