JP2839843B2 - Winding core forming and holding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for holding and forming a wound core used in a transformer or the like, and an object thereof is to provide a core material made of a silicon steel strip or an amorphous magnetic alloy thin strip. When the iron core element wound in a circular shape is formed into a rectangular shape by using the method described above, the rectangular state of the wound iron core is favorably maintained.

[0002]

2. Description of the Related Art Conventionally, as shown in FIG. 8, a core material used for a transformer or the like is formed by cutting an iron core material such as a silicon steel strip, for example, every one turn (one-turn cut method). To form a circular iron core body 1, and a pair of outer molds 2, 3 for press forming inside the iron core body 1.
And the inner mold 4 (the two-dot chain line portion in FIG. 8) is inserted with the inner mold 4 in the middle, and then the inner mold 4 is pressed down by a pressing press or the like. The metal 2 and 3 are pushed up and down in FIG.
Form a substantially rectangular iron core equal to ~ 4. When the iron core element 1 is formed into a rectangular shape, the inner mold 4 and the pair of outer molds 2 and 3 which are in contact with the mold 4 form portions where both molds come into contact with each other in a tapered shape. At the same time, the inner metal mold 4 itself is formed in a wedge shape, and the outer metal molds 2 and 3 are inserted into the iron core body 1 with a space therebetween as shown in FIG. 4 is the outer metal mold 2, 3
As shown in FIG. 9, the iron core body 1 was formed into a rectangular wound iron core 9 by press-fitting between the cores.

Next, as shown in FIG. 9, tightening plates 5 and 6 are applied to the outside of the rectangular core 9 and the bolts 7 and 7a and nut 8 are attached to each other. To maintain the wound iron core 9 in a rectangular shape,
The wound core 9 is subjected to strain relief annealing. After annealing, the fastening plates 5 and 6 and the molds 2 to 4 were removed from the wound core 9 to produce a rectangular wound core 9.

[0004]

In the rectangular molding of the wound core 9, the circular core body 1 is formed into a rectangular shape using the outer and inner molds 2 to 4, and the shape is maintained. For this purpose, fastening plates 5 and 6 are applied to the outside of the leg iron portion and the yoke portion of the rectangularly formed wound iron core 9 each time.
Long bolts 7, 7 a having different lengths are respectively passed through the fastening plates 5, 6 and fastened with nuts 8. That is, as shown in FIG. 9, the fastening plates 5 and 5 are provided on the side of the leg portion of the wound iron core 9, and the fastening plates 6 and 6 are provided on the side of the yoke.
Respectively, and the corresponding fastening plates 5, 5,
6 and 6 with the wound iron core 9 sandwiched between the long bolts 7,
7a were individually fastened. However, the work of attaching the fastening plates 5 and 6 is performed by applying the fastening plates 5 and 6 to the outer periphery of the winding core 9 as shown in FIG. Because it was fastened individually
In a very unstable state, and with a plurality of bolts 7,7
As a result of manually tightening all a, it takes time and effort, and since the work is performed by erecting the iron core, there is a problem in safety, etc., so that the forming work of the wound core 9 is efficiently performed. It was difficult.

In order to maintain the rectangular state of the rectangular core 9, a pair of tightening plates 5, 6 having different lengths is prepared, or these tightening plates 5, 6 are prepared. At least four bolts 7 and 7a for fixing the bolts 7 and 7 to the wound iron core 9, and the tightening plates 5 and 6 and the bolts 7 and 7
Since a is required in advance every time the type of the wound iron core 9 is different, that is, each time the window size is different, the length is different.
Coupled with the troublesome installation of the fastening plates 5 and 6,
Not only is it uneconomical to manufacture the wound iron core 9, but also the types of the fastening plates 5, 6 and the bolts 7, 7a increase,
The storage management is troublesome and the use of different dimensions may be erroneously used. Therefore, the fastening plates 5 and 6 must be carefully attached.

In view of the various problems described above, the present invention provides a single type of holding metal for holding a rectangular state of a rectangularly formed wound iron core, which is provided on the wound iron core by simple means. Another object of the present invention is to provide a winding core forming and holding device having a simple structure capable of smoothly holding a rectangular state of the winding core.

[0007]

According to the present invention, when a circular iron core element is formed into a rectangular shape, for example, the iron core element is formed using a metal fitting formed of a corner die, a leg and a yoke die plate. On the inner peripheral surface of the body, four corner dies are inserted and arranged at positions where the iron core body can be formed into a rectangular shape, and each of the corner dies has a leg iron side and a yoke side of the iron core body, respectively. In the above, a pair of tapered guide grooves is 90 °
Are formed with a spacing of
A pair of leg mold plates are inserted on the leg iron part side, and a pair of yoke mold plates are respectively press-fitted on the yoke part side, and the distributed corner molds are radially pushed to form a circular iron core body. A rectangular core is obtained by rectangular molding.

[0008] On the outer peripheral side of each corner of the rectangular core, a holding metal fitting for holding the core in a rectangular state is attached. This holding metal fitting is formed, for example, by bending a metal material such as a steel plate into an L-shape while making its width slightly longer than the width of the winding core. Applying the outer periphery of each corner portion of the iron core to each of the four holding metal members by tightening the four holding metal members with a tightening band to form a holding metal member to be locked and held on the wound iron core, thereby forming a rectangular shaped wound iron core. Construct a holding device.

[0009]

According to the present invention, when a circular core body is formed, for example, four corner molds are simultaneously pressed in a radial manner using a leg and a yoke mold plate to form a rectangular core body. With the use of the forming metal fittings, since each corner die slides hardly against the inner peripheral surface of the wound core to generate a frictional force, processing distortion hardly occurs during rectangular forming of the wound core.

In the case where the rectangular shape of the wound core is held by the forming and holding metal fittings after the rectangular molding of the circular core body, the metal pieces constituting the forming and holding metal fittings are respectively applied to the outer periphery of the corners of the wound core. Can be easily maintained in a rectangular state by simply tightening the core to the winding core with a tightening band, and the L-shaped bracket piece has a radius of curvature smaller than the radius of curvature of the outer periphery of the corner of the winding core. By setting, the pressing force of the metal piece against the core is a force equivalent to the tightening force of the tightening band by the wedge effect of the metal piece itself acting on the corner of the core, and the linear part of the core. Since it can be easily obtained as a force for pressing the (iron part and yoke part), the iron part and yoke part of the wound iron core can be held in a substantially linear state.

Further, since the forming and holding apparatus of the present invention can be mounted by utilizing the outer periphery of the corner of the wound core,
When the core is annealed, since there is no forming metal or metal piece near the iron leg and the yoke, the core is heated to a predetermined temperature in a short time by using energy economically and efficiently. For example, it is possible to perform the forming and annealing operations of the wound iron core quickly and surely, for example, because it is possible to heat.

[0012]

FIG. 1 shows an embodiment of a molding and holding apparatus according to the present invention.
6 through FIG. First, the metal fitting will be described. In FIG. 2, 11 is a continuous winding of a core material made of a silicon steel strip or an amorphous magnetic alloy ribbon,
Alternatively, an iron core element is formed by cutting every turn and winding it into a circular shape. Reference numeral 12 denotes a tightening band wound around the iron core element 11. Reference numeral 13 denotes a metal fitting for rectangularly forming the circular iron core element 11. As shown in FIGS. 5 and 6, four rod-shaped corner molds 14 and a pair of corner molds 14 interposed between the corner molds 14. As shown in FIG. 5, the leg-shaped plate 15 and the yoke-shaped plate 16 are formed into a rectangular frame.

Next, the details of the molding fitting 13 will be described. First, as shown in FIG.
A metal bar having a predetermined diameter is cut at a size slightly longer than the axial length of the core body 11, and the two guide grooves 17 are formed on the bar at an interval of 90 °. , 17a
Are drilled in parallel at a required angle of inclination (tapered shape), with the leg-shaped plate 15 in one guide groove 17 and the yoke-shaped plate 16 in the other guide groove 17a. It is formed with a width dimension that can be inserted and removed.

The leg mold plate 15 and the yoke mold plate 16 fitted in the guide grooves 17 and 17a of the corner mold 14 have substantially the same length as the corner mold 14, respectively. Its thickness is tapered guide groove 17,
The guide groove 17 is formed in a trapezoidal shape with a width dimension that allows it to be inserted and removed so that it can be inserted into and removed from the groove 17a, and the side end is inclined at the same angle as the tapered portion of the guide groove 17, 17a.

Next, the metal mold 18 will be described.
As shown in FIGS. 1 and 4, the forming and holding bracket 18 includes four metal pieces 19 and a tightening band 20 which are engaged and held on the outer periphery of each corner of the rectangular core B. Each of the metal pieces 19 is secured to the core B by using a tightening band 20.
Are fixed to the winding core B by engaging with the four corners of the winding core B. The width dimension of the metal pieces 19 is the same as the axial length of the winding core B, or slightly. The width dimension shall be wide and the length dimension shall be the length covering the corner of the wound core B. The radius of curvature of a metal plate such as a steel plate shall be smaller than the radius of curvature of the outer periphery of the corner of the wound core B. However, the angle is formed by bending in an L-shape at about 90 °. As shown in FIG. 4, when the metal pieces 19 are engaged with the corners of the wound iron core B, both ends of the bent portion are formed on the outer peripheral edge of the corner mold 14 as shown in FIG. It is formed in an L-shape with a length slightly protruding therefrom.

Next, a case where the molding and holding apparatus of the present invention is used will be described. First, a description will be given of a case where the iron core element 11 wound in a circular shape is formed into a rectangular shape by using the metal fitting 13. At the time of forming the rectangle, as shown in FIG. 2, four corner dies 14 are provided on the corner dies 14 at positions corresponding to the corners of the circular core body 11.
In a state where the guide grooves 17 and 17a of the strip are opposed to each other, they are arranged so that a rectangular frame can be formed in the iron core body 11. In this case, the corner mold 14 is provided with the guide grooves 17, 17.
The portion at the position where the tapered groove of “a” is shallow is arranged in the iron core body 11 with its upward direction. Thereafter, in FIG. 2, the opposing guide grooves 17, 1 between the upper and lower portions of the corner mold 14 are formed.
7, a pair of leg mold plates 15, 15 is inserted, and guide grooves 17 of corner molds 14 facing each other in the left-right direction in FIG.
A pair of yoke templates 16, 16 are inserted between a, 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 each pair 6 is inserted, each mold plate 15, 16 is simultaneously pressed downward by a pressing means (pressing device) (not shown) to be pressed into the required corner mold 14. Each corner mold 14 arranged in the iron core body 11 has a trapezoidal leg and yoke mold plates 15, 16 formed with guide grooves 17, 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. At this time, the corner mold 14 is pushed in the direction of the arrow in FIG. 2 as the trapezoidal legs and the yoke mold plates 15 and 16 descend in the guide grooves 17 and 17a. Since the surface hardly slides, mechanical processing distortion is generated by the rectangular forming of the core element body 11 at the corner of the inner peripheral surface of the wound core B formed into a rectangular shape by the pressing of the corner mold 14. Can be greatly suppressed.

Next, a description will be given of a case where the rectangular shape of the rectangularly formed wound core B is held by the forming and holding fitting 18. Even if the wound core B is formed into a rectangular shape by using the forming metal 13, the outer peripheral surfaces of the leg iron portion (leg) and the yoke portion (yoke) are often not straight but curved. .
In this state, on the outer periphery of each corner of the outer peripheral surface of the core B,
As shown in FIGS. 1 and 4, 4
The individual metal pieces 19 are applied. As shown in FIG. 4, these metal pieces 19 are formed by bending a metal plate such as a steel plate at an angle close to a right angle. When the metal pieces 19 are applied to the outer periphery of the corner of the wound core B, as shown in FIG. Since it is formed in advance so as to have a radius of curvature smaller than the radius of curvature of the outer periphery of the corner portion of the wound core B, a void S is formed between the inside of the metal piece 19 and the outer top of the corner portion. Becomes Also, FIG.
Since the width of the metal piece 19 is slightly longer than the axial dimension of the core B, the metal piece 19 is mounted in such a manner as to project upward from one end face of the core B.

As described above, the metal piece 19 is wound around the core B
1, the fastening band 20 is wound from the outside of each metal piece 19 to fix the metal piece 19 to the core B, as shown in FIG. Is held in a rectangular state by the forming and holding metal fittings 18 composed of the metal pieces 19. And in the present invention,
When the metal pieces 19 are arranged on the outer periphery of each corner of the wound core B and fastened to the outer circumference of the corner of the wound core B by the fastening band 20, each metal piece 19 is free at both ends of the bent portion. At the end, the tightening force of the tightening band 20 is effectively received, so that the leg portion and the yoke portion of the core B can be maintained in a straight line. When the winding core B is in a rectangular holding state,
The reason why the force for linearly pressing the leg iron portion or the like is given can be obtained by the following calculation formula.

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

[0021]

(Equation 1)

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

This is substituted into the calculation formula shown in the equation (1) of the equation (1).

[0023]

(Equation 2)

The above

According to the equation (2), the tightening force 6 of the tightening band 20 is
The reaction force R was found to be about 331 kg for 00 kg. As a result, as shown in FIG.
The reaction force R applied to the portion (the edge of the corner) is balanced with the force applied to the free end of the metal piece 19 obtained by the tightening force of the tightening band 20. Therefore, the metal piece 1
9, ie, the force applied to the Y portion in FIG.
Since the weight becomes 31 kg, L-shaped metal pieces 19 are arranged at each corner of the wound core B, and these pieces are tightened with a tightening band 20 having a tightening force of 600 kg. The pressing force of about 331 kg obtained in step (1) can press the part of the outer periphery of each corner of the core B, which is in contact with the metal piece 19, toward the corner mold 14, so that the leg iron portion and the yoke of the core B The portion can be pressed and urged substantially linearly, and the rectangular state of the wound core B after the rectangular molding can be satisfactorily held without requiring a specially large force.

As described above, the radius of curvature of the metal piece 19 for pressing and urging the leg portion and the yoke portion of the core B in a straight line is, as shown in FIG. , The pressing force obtained at the free end of the metal piece 19 can be easily obtained by a wedge action. As a result, the tightening force of the tightening band 20 is effectively used. The rectangular shape of the wound core B can be maintained.

After the rectangular forming operation of the wound core B is completed as described above, annealing is performed with the forming holding metal fittings 18 and the forming metal fittings 13 provided on the wound core B to remove distortion of the whole wound core B. I do. After the annealing, the wound core B is first disassembled by releasing the fastening of the tightening band 20 and separating the metal piece 19 from the corner of the wound core B. Each of the legs 15 and 16 of the yoke is pulled out of the corner die 14 from the inside of the B, and thereafter, the corner die 14 is finally removed to eliminate the formed and held state of the wound core B.

According to the present invention, as the molding fitting 13, a rod-shaped corner mold 14 and a plate-like leg and yoke mold 1 are used.
Although the example using 5 and 16 has been described, the present invention is not limited to this, and the circular iron core element 11 is formed into a rectangular shape using a metal fitting formed of a conventionally used wedge-shaped press-forming die. You may do so. L-shaped bracket piece 1
9 may of course be a L-shaped one formed by combining a pair of plate members at right angles without bending a steel plate or the like into an L-shape.

[0028]

Since the present invention is configured as described above, it has the following effects. (1) According to the present invention, a metal piece having a planar shape formed into an L-shape is applied to the outer periphery of a corner portion of a rectangularly formed wound core, and the piece is integrally fastened to the wound core by a fastening band. Since the rectangular state of the winding core was maintained,
Compared to the case where the rectangular state of the wound core is maintained by using the tightening plate and the bolt as in the related art, the rectangular holding work of the rectangularly formed wound core can be performed quickly, easily, and economically. it can.

(2) According to the present invention, when the rectangular shape of the wound core is maintained, a molded holding fitting can be formed by using an L-shaped fitting piece and a tightening band, which is convenient. At the same time, since the bending angle of the metal piece is smaller than the angle of the outer periphery of the corner of the wound core, the tightening force of the tightening band can be effectively used at the edge of the corner of the wound core. The iron core itself can be pressed from outside with a constant force. That is, as a result that the wedge action can be effectively applied to the metal piece, the coiled core is 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 are more formed. Since it can be pressed and urged in a linear state, the rectangular holding means for the wound core can be manufactured easily and at low cost.

Further, since the metal piece has a width corresponding to the axial dimension of the wound core equal to or longer than the width of the wound core, a force for pressing the wound core acts. However, the wound core is not damaged at all, and the wound core can be effectively kept in a rectangular state with a uniform force, which is convenient. In addition, when the metal piece is attached to the outer periphery of the corner of the wound iron core, the fastening band may be fastened without erecting the wound iron core, so that the mounting operation of the molded holding metal can be performed safely.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a use state of a wound iron core forming and holding device of the present invention.

FIG. 2 is an explanatory view showing a state in which a molding metal is inserted into a circular iron core body to form a wound iron core in a rectangular shape 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 using a forming metal fitting.

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

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

FIG. 6 is a perspective view of a corner mold forming a part of a molding fitting.

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

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

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

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Iron core body 13 Molding fitting 14 Corner mold 15 Leg mold plate 16 Yoke mold plate 17, 17a Guide groove 18 Molding holding metal fitting 19 Metal fitting piece 20 Tightening band

Claims (3)

(57) [Claims] 1. A rectangular core formed by winding a core material such as a silicon steel strip in a circular shape and forming the core element into a rectangular shape by using a metal mold. Metal pieces formed in an L-shape are disposed around the outer periphery of each of the corners, and these metal pieces are immovably fastened to the winding core with a tightening band to hold the winding core in a rectangular state. A forming and holding device for a wound iron core, comprising a forming and holding metal fitting comprising the L-shaped metal piece and a tightening band. 2. A metal piece constituting a forming and holding metal member arranged at each corner of the wound core is formed so that its width is equal to or slightly longer than the axial length of the wound core. The device for holding and forming a wound core according to claim 1, wherein: 3. A metal piece constituting a holding metal member arranged at each corner of the wound core, when formed in an L-shape, has a radius of curvature smaller than the radius of curvature of the outer periphery of the corner of the wound core. 2. The device according to claim 1, wherein the device is bent.