JP3348058B2 - Laminated core and mold equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated core used for a stator or a rotor of a transformer or an electric motor, for example.
And a mold device for stacking and integrating the laminated cores.

[0002]

2. Description of the Related Art In a conventional laminated core of this kind, a plurality of plate-like magnetic members are generally formed with protrusions by extrusion in the thickness direction thereof, and thereby formed on the back side of each protrusion. The projections of the other plate-shaped magnetic members are press-fitted into the recessed portions, and the respective plate-shaped magnetic members are sequentially stacked to be integrally fixedly formed. However, as described above, in the case of a laminated core that is laminated by press-fitting and fixing the entire circumference of the protrusion and the recessed portion, even if the accuracy of the mold device is increased, the longitudinal direction of the plate-shaped magnetic member by punching and crimping can be achieved. Is slightly displaced, and the error accumulates in proportion to the number of stacked layers.

As shown in FIG. 6, for example, a protruding portion 1b is press-fitted into a concave portion 1a of a plate-shaped magnetic member 1 having a thickness of 0.5 mm, and 200 sheets are successively stacked to form a laminated core having a thickness of about 100 mm. Is obtained, if the accuracy of the first stage of the caulking is 0.0
Assuming that the accuracy is 01 mm, the deviation of the entire laminated core is simply 0.001 mm × 200 = 0.2 mm,
As a result, the laminated core has a total of 0.2
mm. And, due to this inclination, for example, when applied to a rotating machine, since the air gap between the rotor and the stator becomes non-uniform, noise and vibration are generated and the characteristics are degraded. When applied to a transformer, there are problems such as unbalance and gaps in the magnetic path, which may cause deterioration of characteristics and generation of beats.

Therefore, for example, Japanese Patent Application Laid-Open No. Sho 59-139838 discloses
Japanese Patent Application Laid-Open Publication No. H11-64300 and the like disclose that, as described below, by providing several press-fit portions on the inner peripheral surface of the recessed portion, a laminated core that does not tilt even when laminated while being eccentric is proposed. 7 and 8 are views showing the configuration of a die and a punch constituting the mold apparatus. FIG. 9 shows the configuration of a plate-shaped magnetic member having a recess and a projection formed thereon. FIG. 10B is a cross-sectional view taken along line BB in FIG. 10A, and FIG. 10 is a cross-sectional view showing a state where the plate-shaped magnetic members in FIG. 9 are stacked. In FIG, 2 is a die having a circular shape of the hole 2a of the inner diameter d _1, 3 a plurality of recesses 3a, such as the diameter of the inscribed circle to the outer peripheral surface has an outside diameter d ₂ is d ₃ is formed And the outer diameter d ₂ of the punch 3 is the die 2
Of greater than the inner diameter d ₁ of the holes 2a, the diameter d ₃ of the inscribed circle of each recess 3a is formed from the inner diameter d ₁ of the holes 2a 5 to 40 microns small.

[0005] Then, as shown in FIG. 9, the plate-shaped magnetic member 4 is formed by the die 2 and the punch 3 configured as described above.
When the protrusions 6 of the other plate-shaped magnetic member 4 are press-fitted into the recesses 5 formed respectively in the recesses 5 as shown in FIG.
Since the inner diameter D ₁ of the is larger than the outer diameter D ₂ of the protrusions 6, the clearance C
Bonding strength can not be obtained in this range occur, also because the protrusions the outer diameter D ₂ of 6 larger than the diameter D ₃ of the inscribed circle of the projections 5a formed on the inner peripheral surface of the recess 5, the press-fitting At this time, a lateral pressure is generated, and a fixing force is obtained in this range, and the respective plate-shaped magnetic members 4 are sequentially fixed and laminated integrally.

[0006]

The conventional laminated core has a die 2 having a perfect circular hole 2a as described above, and a depression 5 punched by a punch 3 having a plurality of depressions 3a formed on the outer periphery. The projection 6 is fixedly integrated by press-fitting and punching and swaging. However, in general, the rigidity is lower than that of the die 2, and since the recess 3 a is machined on the side of the thin punch 3 having an outer diameter of 0.6 mm to 2.0 mm, sufficient rigidity cannot be expected. There has been a problem that the precision of staking is reduced.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and provides a laminated core and a mold apparatus capable of preventing a decrease in the rigidity of a mold and improving the precision of staking. It is intended to do so.

[0008]

According to a first aspect of the present invention, there is provided a laminated core in which a plurality of plate-like magnetic members are each formed with a projection by extruding in the thickness direction thereof, and each of the depressions formed thereby. The protrusions of the other plate-shaped magnetic members are press-fitted into the portion, and the outer diameter of the protrusions is smaller than the inner diameter of the recess by a predetermined dimension in the laminated core integrated by sequentially stacking the respective plate-shaped magnetic members. A plurality of protrusions are formed on the outer periphery of the protrusion so that the diameter of the circumscribed circle is larger than the inner diameter of the recess by a predetermined dimension, and the protrusion is fixed by press-fitting and the inner peripheral surface of the recess is fixed. It is intended to be.

According to a second aspect of the present invention, there is provided a laminated core according to the first aspect, wherein the protrusions are evenly arranged on the outer periphery of the protrusion.

The laminated core according to a third aspect of the present invention is the laminated core according to the first or second aspect, wherein the projection is formed in an arc shape.

According to a fourth aspect of the present invention, there is provided a punch having a circular cross section and an inner diameter smaller than the outer diameter of the punch by a predetermined dimension coaxially with the punch. And a die having a plurality of depressions formed on the inner periphery of the hole such that the diameter of the inscribed circle is larger than the outer diameter of the punch by a predetermined dimension.

According to a fifth aspect of the present invention, there is provided a mold apparatus according to the fourth aspect, wherein the depressions are evenly arranged on the inner periphery of the hole.

According to a sixth aspect of the present invention, there is provided a mold apparatus according to the fourth or fifth aspect, wherein the depression is formed in an arc shape.

According to a seventh aspect of the present invention, there is provided a mold apparatus according to the sixth aspect, wherein the recess is formed by wire electric discharge machining.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a cross-sectional view showing a configuration of a main part of a laminated core according to Embodiment 1 of the present invention. FIG. 2 shows a configuration of a crimped portion of a plate-shaped magnetic member in FIG. FIG. 3B is a plan view, FIG. 3B is a cross-sectional view, FIG. 3C is a plan view of a projection side, FIG. FIG. 4 is a cross-sectional view showing a step of crimping a plate-shaped magnetic member by a die and a punch, and FIG.

In the figure, reference numeral 7 denotes a recess 8 and a projection 9
There in the plate-shaped magnetic member formed respectively on the front and back surfaces, recess 8 is in the perfect circular shape having an inner diameter D _1, also projections 9 about 20 microns than the inner diameter D ₁ of the outer diameter D ₂ is recessed portion 8 smaller And the diameter D ₃ of the circumscribed circle on the outer circumference is 10 to 10 times larger than the inner diameter D _{1 of the} recess 8.
A plurality of protrusions 9a each having a size of 15 μm are formed, and the tip of each protrusion 9a has a radius of 0.1 to 0.1 μm.
Each is formed in a 0.2 mm arc shape.

A punch 10 for forming the recess 8 has an outer diameter D ₄ which is the same as the inner diameter D ₁ of the recess 8. 11 is a die which constitutes the mold apparatus with the punch 10 has a smaller inner diameter D ₅ from about 20 microns outer diameter D ₄ of the punch 10 in a central portion, the outer diameter D ₆ of the circumscribed circle on the inner peripheral punch 10 through holes 12 are formed having a plurality of recesses 12a as 10-15 microns greater than the diameter D _4. The tip of each recess 12a has a radius of 0.1 to 0.1.
Each is formed in a 2 mm arc shape.

As described above, in the first embodiment,
The outer diameter D ₂ of the protruding portion 9 of the plate-shaped magnetic member 7 which is formed by the through hole 12 of the die 11, as well as than the inner diameter D ₁ of about 20 microns small recess 8 which is formed by the punch 10, the outer periphery a plurality of protrusions 9a as 10-15 microns greater than the inner diameter D ₁ of the diameter D ₃ is recessed portion 8 of the circumscribed circle formed respectively, press-fitting the projections 9 into the recessed portion 8 of the other plate-shaped magnetic members 7 By repeating this operation sequentially, a large number of plate-shaped magnetic members 7 are laminated and integrated to form a laminated core.

Therefore, (the diameter D of the circumscribed circle of the projection 9a)
₃₎ - fixing force moieties present, i.e. the interference portion b shown in FIG. 5, by inner surfaces of the tips of the projections 9a and recess 8 is interference, plastically deformed during the (inner diameter D ₁ of the recess 8) On the other hand, a fixing force cannot be obtained in a portion existing between (inner diameter D ₁ of recess 8) − (outer diameter D ₂ of protrusion 9), that is, in gap C shown in FIG. 5.

As described above, according to the first embodiment, the inner diameter D ₁ of the depression 8 of the plate-shaped magnetic member 7 and the outer diameter D _{2 of the} projection 9
And a diameter D ₃ of the circumscribed circle of the projections 9a by setting the value of the relationship as described above, partially because as fixed by interference portions b to have a clearance a, the plastic deformation of the interference portions b Due to the difference in the amount, the center of the recess 8 and the center of the protrusion 9 are prevented from trying to match each other, and are stacked while being eccentric according to a blank die (not shown). Noise and vibration, which can be problematic when applied to rotating machines,
In addition, it is possible to prevent the occurrence of a beat, which is a problem when applied to a transformer.

Further, since the projections 9a are evenly arranged on the outer periphery of the projection 9, even when the centers of the projections 9 are deviated in any direction when the projections 9 are pressed into the depressions 8, the projections 9a and the projections 9a are displaced. Can eliminate the force that attempts to match the centers of the two, preventing the inclination. In addition, since the projection 9a is formed in an arc shape, the range of the interference portion b can be made small, Even if the center of the recess 8 and the center of the protrusion 9 are shifted, a difference in the amount of plastic deformation of the interference portion b occurs, and the force that the two centers try to match can be eliminated, and the same effect as above can be obtained. Become.

Further, a recess 12a is provided on the side of the through hole 12 of the die 11 having relatively high rigidity, and a projection 9a serving as an interference portion b between the recess 8 of the plate-shaped magnetic member 7 and the projection 9 is formed. Since it is formed, it is possible to improve the accuracy of the swaging. In addition, by forming the shape of the recess 12a of the through hole 12 of the die 11 for forming the projection 9a of the projection 9 by wire electric discharge machining, a number of the recesses 12a are formed.
Can be processed finely and with high precision. or,
In the above configuration, the cross-sectional shape of the recess 8 and the protrusion 9 is described as being circular, but the present invention is not limited to this.
For example, the cross-sectional shape may be rectangular, square, or the like, and the same effects as described above can be obtained.

[0023]

As described above, according to the first aspect of the present invention, projections are formed on a large number of plate-like magnetic members by pushing them out in the thickness direction thereof, and the respective recesses formed thereby are formed. The outer diameter of the projection is formed smaller than the inner diameter of the recess by a predetermined size in the laminated core integrated by press-fitting the projections of the other plate-shaped magnetic members into each other and sequentially stacking the respective plate-shaped magnetic members. While forming a plurality of protrusions on the outer periphery of the protrusion such that the diameter of the circumscribed circle is larger than the inner diameter of the recess by a predetermined dimension,
Since the tip of the projection and the inner peripheral surface of the depression are fixed by deformation by press-fitting, it is possible to provide a laminated core capable of preventing the lamination inclination and of improving the punching accuracy, as well as preventing the lamination inclination. it can.

According to a second aspect of the present invention, in the first aspect, the protrusions are evenly arranged on the outer periphery of the protrusion, so that the stacking inclination can be prevented, and furthermore, the crimping can be performed. A laminated core capable of improving the accuracy can be provided.

According to a third aspect of the present invention, in the first or second aspect, the projections are formed in an arc shape, so that it is possible not only to prevent the stacking inclination but also to improve the punching accuracy. It is possible to provide a laminated core that can be achieved.

According to a fourth aspect of the present invention, a punch having a circular cross section and a hole having an inner diameter smaller by a predetermined dimension than the outer diameter of the punch are provided coaxially with the punch and coaxial with the punch. Since the die is formed and has a plurality of depressions formed on the inner periphery of the hole such that the diameter of the circumscribed circle is larger than the outer diameter of the punch by a predetermined dimension, the inclination of the laminated core can be prevented. That is, it is possible to provide a mold device capable of improving the accuracy of the swaging.

According to the fifth aspect of the present invention, in the fourth aspect, the recesses are evenly arranged on the inner circumference of the hole, so that the metal which can further improve the accuracy of the swaging is provided. A mold device can be provided.

According to a sixth aspect of the present invention, there is provided a mold apparatus according to the fourth or fifth aspect, wherein the recess is formed in an arc shape, so that the punching accuracy can be further improved. Can be.

According to a seventh aspect of the present invention, in the sixth aspect, the dent is formed by wire electric discharge machining, so that a mold device having a fine and highly accurate dent is provided. Can be.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a configuration of a main part of a laminated core according to Embodiment 1 of the present invention.

2A and 2B show a configuration of a crimping portion of the plate-shaped magnetic member in FIG. 1, wherein FIG. 2A is a plan view of a recessed portion, FIG. 2B is a cross-sectional view, and FIG. .

3A and 3B show a configuration of a die constituting a main part of the mold apparatus, wherein FIG. 3A is a sectional view and FIG. 3B is a plan view.

FIG. 4 is a cross-sectional view showing a step of crimping a plate-shaped magnetic member with a die and a punch.

FIG. 5 is a diagram showing details of an interference portion caused by press-fitting of a depression and a projection.

FIG. 6 is a cross-sectional view showing a state where the plate-shaped magnetic members are tilted by being laminated.

7A and 7B show a configuration of a die constituting a main part of a conventional mold apparatus, wherein FIG. 7A is a sectional view and FIG. 7B is a front view.

8A and 8B show a configuration of a punch constituting a main part of a conventional mold apparatus, wherein FIG. 8A is a side view and FIG. 8B is a front view.

9A and 9B show a configuration of a conventional plate-shaped magnetic member in which a depression and a projection are formed, and FIG. 9A is a plan view of the depression.
(B) is a cross-sectional view along line BB in (A).

10 is a cross-sectional view showing a state where the plate-shaped magnetic members in FIG. 9 are stacked.

[Explanation of symbols]

7 the plate-shaped magnetic member, 8 recess 9 projections, 9a protrusions, D ₁ recess inner diameter of the outer diameter of D ₂ projections, of the circumscribed circle of D ₃ projection diameter, 10 punches, 11 die, 12
Through hole, 12a depression, a gap, b interference part.

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H02K 1/18 H02K 15/02 H02K 15/03

Claims (7)

(57) [Claims] 1. A plurality of plate-like magnetic members each having a protrusion formed by being pushed out in the thickness direction thereof, and each of the protrusions of another plate-like magnetic member being press-fitted into each of the recesses formed thereby. In the laminated core integrated by sequentially stacking the plate-shaped magnetic members, the outer diameter of the protrusion is formed smaller than the inner diameter of the recess by a predetermined dimension, and a circumscribed circle is formed on the outer periphery of the protrusion. A plurality of protrusions are formed such that the diameter of the protrusions is larger than the inner diameter of the recessed portion by a predetermined dimension, and the protrusion is fixed to the inner peripheral surface of the recessed portion by press-fitting. And a laminated core. 2. The laminated core according to claim 1, wherein the protrusions are evenly arranged on the outer periphery of the protrusion. 3. The laminated core according to claim 1, wherein the projection is formed in an arc shape. 4. A punch having a circular cross-section and a hole having an inner diameter smaller than the outer diameter of the punch by a predetermined dimension coaxially with the punch. A mold apparatus comprising: a die having a plurality of depressions formed on an inner periphery thereof such that a diameter of a circumscribed circle is larger than an outer diameter of the punch by a predetermined dimension. 5. The mold apparatus according to claim 4, wherein the depressions are evenly arranged on the inner periphery of the hole. 6. The mold device according to claim 4, wherein the depression is formed in an arc shape. 7. The mold apparatus according to claim 6, wherein the depression is formed by wire electric discharge machining.