JPH02137207A - Pack of lamination and formation of protruding section and recessed section - Google Patents

Abstract

PURPOSE: To improve electric efficiency and to attain cost reduction by mutually connecting respective adjacent laminations at one position. CONSTITUTION: Each lamination has one recessed part 3 and one protruding part 4, and these parts are lined up on a common axis vertical to the lamination. The protruding part of one lamination is protruded inside the recessed part of its adjacent lamination. The pack of such laminations 5 is installed on a lamination 6 called a partition plate. The pack of laminations has torsional flexibility by connecting the respective laminations only through the single protruding part and recessed part. Then, depth P of the recessed part 3 on each lamination is about 69% of thickness T of materials for the lamination. The edge of the recessed part 3 is formed from a curved surface having a radius R. The recessed part is made columnar and a height H of this columnar protruding part 4 is about 65% of the thickness T of the materials.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a pack of laminations for electromagnetic devices, a lamination used in the pack,
The present invention relates to a method for manufacturing such a pack, an apparatus for manufacturing the pack, and an electromagnetic device equipped with the pack.

In another aspect, the invention relates to the formation of protrusions and recesses.

(Prior Art and its Problems) Various methods have been proposed for manufacturing lamination packs or stacks for electromagnetic devices.

One known method is to rigidly connect each lamination to adjacent laminations by multiple connections. However, with that method, the magnetic flux path is interrupted at each connection point.

Furthermore, when two such packs are joined together in their faces, an air gap is always found between the pole iron faces formed by the packs.

Due to the interruption of the magnetic flux path and the presence of air gaps, there are several problems in adapting the electromagnetic specifications to the device. One solution to this problem has been proposed to be the use of better quality materials, but this increases expense. Other proposals have also been made to use plates or laminations in an unconnected state, but this increases costs due to the need for expensive assembly equipment.

SUMMARY OF THE INVENTION The present invention is a pack of laminations for torsionally flexible electromagnetic devices.

In the present invention, the i-contact laminations are connected to each other at one point.

The present invention is a pack of laminations for electromagnetic devices, each lamination having one recess on one side and one protrusion on the other side on a common axis perpendicular thereto,
Puncture of laminations in which each lamination is connected by one protrusion protruding into one recess of an adjacent lamination.

The present invention provides the pack in which (a) the recess and the protrusion of each lamination are cylindrical, and/or (b) the base of the protrusion is a curved surface, and/or (t) the base of the protrusion is cylindrical. and/or (1) the edge of the recess is a curved surface.

and/or (e) the depth of the recess is greater than 50% of the thickness of the lamination, the height of the protrusion is greater than 50% of the thickness of the lamination, and less than the depth of the recess;
and/or (force) the depth of the recess is approximately 69% of the thickness of the lamination, the height of the protrusion is approximately 65% of the thickness of the lamination, and/or (g) the pack further comprises a partition plate. It is equipped with

The present invention is a method of manufacturing a pack of laminations for electromagnetic devices, each by protruding one protrusion on one side of the lamination into one recess on the other side of the adjacent lamination. A method of manufacturing a pack of laminations comprising making connections between the laminations and adjacent laminations.

The present invention allows the lamination to be formed with a protruding edge by pressing a recess-forming punch against the lamination.
Preferably, the recess is formed to have a depth of about 69% of the thickness of the lamination.

The protrusions are formed to have a height of approximately 65% of the thickness of the lamination.

The present invention is an apparatus for manufacturing packs of laminations for electromagnetic devices, in which on each lamination one recess is formed on one side and one recess on the other side on its vertical common axis. means for forming protrusions and means for connecting each lamination with an adjacent lamination by protruding one protrusion on one side of the lamination into a recess on the other side of the adjacent lamination; Equipment for producing lamination packs for electromagnetic devices with.

In the present invention, the forming means is provided with a protrusion forming punching die having a five-curved surface or a conical sloped edge.

Furthermore, means were provided for pushing the protrusion beyond the edge into the die.

The present invention is a lamination for an electromagnetic device, comprising a recess on one side of the lamination and a protrusion on the other side on a common axis perpendicular to the lamination; A lamination having a structure in which the protrusions are connected to adjacent laminations only by protruding into the recesses of the adjacent laminations.

In the lamination, the present invention provides that (a) the recess and the protrusion are cylindrical, and/or (b) the base of the protrusion is a curved surface, and/or (t) the base of the protrusion has a truncated conical slope. and/or (1) the edges of the recess are curved, and/or (e) the depth of the recess is greater than 50% of the thickness of the lamination, and the height of the protrusion is 50% of the thickness of the lamination. % and less than the depth of the recess, and/or the depth of the recess is about 69% of the thickness of the lamination and the height of the protrusion is about 65% of the thickness of the lamination. It is.

The present invention is a method of forming protrusions and/or recesses in a sheet of ductile material by pressing a punch into the material and punching the punch over the curved surface or frustoconical slope of a protrusion-forming die. A method of forming protrusions and/or recesses in a sheet of ductile material comprising extruding the protrusions during a cutting die.

In the present invention, the height of the protrusion and/or the depth of the recess is about 65% to about 70% of the thickness of the material.

The present invention provides an electromagnetic device comprising the lamination pack according to any one of claims 1 to 4.

In one aspect of the invention, packs or stacks of laminations connected to each other are provided.

The pack is torsionally or against torsion.
ionally) flexible.

In embodiments, each lamination is connected to an adjacent lamination at one point.

It is known to connect laminations by inserting them into recesses in adjacent laminations using projections provided thereon. Such protrusions and recesses are punched out of the lamination. Their height or depth is approximately 50 mm of the lamination thickness
% or less.

Height of protrusions/recesses punched out of lamination/
When the depth is approximately 50% of the thickness of the lamination, the protrusion/recess becomes susceptible to breakage and detachment from the lamination (
Become. The inventors have found that the production of protrusions/recesses with a height/depth greater than 50% of the thickness of the lamination is suitable.

In another aspect of the invention, a method of forming protrusions/recesses in a sheet of ductile material is provided. The method involves driving a punch into the material.

including extruding the protrusion over the edge of the protrusion-forming die and into the die. The edge is a curved surface or a frustoconical slope.

In one embodiment of the method of the invention, the height of the protrusion and/or depth of the recess so formed is about 50% to 70% of the thickness of the material.

Protrusions and/or recesses formed by the method described above are used in the embodiments described above. However, it can also be used in other situations for lamination connections.

Further aspects of the invention are set forth in, and reference is made to, the appended claims.

EXAMPLES In order to better understand the invention, and to show how one may carry it out, examples will now be described with reference to the accompanying drawings, in which: FIG.

In FIG. 1, the electromagnetic device is a choke assembly having two packs of 2, e.g. "
A pole face 7 is formed by the surface of the protruding part of the E-shaped lamination. The two packs are arranged so that their pole faces are in contact with each other. There is an open space between the two opposing E-shaped central protrusions of the lamination.

An air gap 8 having a predetermined width is formed.

A magnetic flux is created during lamination by the induction coil 9.

When each lamination is fixedly connected at a plurality of locations, an air gap is necessarily created between the abutting magnetic pole surfaces 7. Furthermore, the magnetic flux path is interrupted by the plurality of connection points.

In one embodiment of the invention, each lamination in each pack is connected to an adjacent lamination at only one point, so that the pack is torsionally flexible. therefore.

The torsional flexibility reduces, if not completely eliminates, undesirable air gaps in the pole faces 7 when the two pucks are brought into abutment as shown in FIG. Furthermore, by reducing the number of connections between laminations, there are fewer disruptions to the magnetic flux path. As a result, electrical efficiency is higher than in packs in which laminations of the same material are fixedly connected at multiple points.

loose or unfixed (unconnected)
When compared to using plates, the electrical efficiency is similar but the cost is less.

In FIG. 2, each lamination comprises one recess 3 and one protrusion 4, which are aligned on a common axis perpendicular to the lamination. The protrusion of one lamination projects into the recess of the adjacent lamination. 50 bags of such lamination.

Lamination 6, herein referred to as partition plate
is installed on top. The partition plate 6 is provided with through holes 2 instead of the combination of the recesses 3 and the protrusions 4. The protrusion of the lowermost lamination 5 projects into the 1 through hole 2.

The lamination pack according to the above embodiment of the present invention includes:
Although each lamination is connected only by a single protrusion and recess, the stresses imposed by subsequent manufacturing processes that include high temperature processing.

and must be able to withstand radial movement to add torsional flexibility to the pack.

The torsional flexibility allows joining of each pole face 7 without any visible air gap along the entire length of the pack, thus maintaining a predetermined air gap 8 (if applicable). Ru.

In order to achieve the above-mentioned resistance, the recesses and protrusions of the lamination have the shapes shown in FIGS. 3 and 4.

The depth P of the recess 3 of each lamination is approximately 69% of the thickness T of the material of the lamination. The edge of the recess 3 has a radius R
It is formed of a curved surface. The recess is cylindrical.

Since the inner diameter of the recess is smaller than the diameter of the corresponding protrusion, interference occurs in the fitting portion.

The height H of the cylindrical protrusion 4 is approximately 65% of the material thickness T.
It is. The base of the protrusion 4 has one of the following shapes.

a) It is formed of a curved surface having a radius r1 smaller than the radius R of the edge of the recess as shown on the right side of FIG.

b) As shown in the left part of FIG.

It is formed with a truncated conical slope C1 having a size similar to the radius r1 of the curved surface.

The radius r1 of the truncated conical slope C1 or curved surface is:

Since it does not collide with or exceed the radius R of the edge of the recess, the engagement between the protrusion and the recess is perfect and air gaps between the sides of the pack are prevented.

In FIGS. 3, 5 and 6, the partition plate 6
The hole 2 has a similar shape to the recess 3 of the lamination, except of course that it passes through the plate 6. The projection 4 of the lowest lamination 5 therefore engages with the partition plate in a manner similar to the engagement with the recess 3 of the lamination.

In FIG. 7, the recesses 3 and protrusions 4 of each lamination are made, for example, in the following manner according to another aspect of the invention.

The metal strip 1 is cut into a punching die 14 in the manner described below.
It is placed on the top of the machine and fixed. The die defines the shape of the vertical cylindrical opening.

The edge of the cylindrical opening has one of the following shapes.

a) It is formed by a curved surface with radius r as shown in the right part of FIG.

b) It is formed by a truncated conical slope C as shown in the left part of FIG.

The recess-forming punch 13 forms the recess 3 and simultaneously projects the metal of the strip 1 beyond the two truncated conical slopes C or curved surface r into the protrusion-forming die 14.

Damage due to shear stress, which is normally observed at approximately 50% of the metal thickness T, occurs on the curved surface r of the edge of the punching die 14 or on the truncated conical slope C.
A recess with a depth P of 69% of the metal thickness T and 65% of the thickness T without causing damage
A protrusion is formed having a height of . The 4% difference between the depth P of the recess and the height H of the protrusion indicates that the metal is compressed and thinned when it is extruded through the truncated conical slope C or curved surface into the protrusion forming die 14. This provides a smooth finish around the protrusion.

The inner diameter of the protrusion forming punch 14 is larger than the outer diameter of the recess forming punch 13 by 0.022 mm. By extruding the metal into the protrusion forming punching die 14 through the 5-conical truncated slope C or the curved surface r, the diameter of the recess is reliably 0.004 mm smaller than the diameter of the recess punch 13. This ensures that the protrusion 0.0 on the part that fits into the recess 3 of 4.
26 mm of interference occurs. The frustoconical bevel C1 or curved surface r applied to the edge of the protrusion-forming punching die 14 forms a frustoconical bevel C1 or curved surface r1 of similar size at the base of the protrusion 4.

At the base of the protrusion 4, a truncated conical slope C is formed as a result.
1 or the curved surface r is smaller than the radius R of the curved surface formed at the opening of the recess 3. Therefore, perfect engagement between the protrusion 4 and the recess 3 is possible, ensuring that no gaps are visible between the respective metal plates, and as a result, the multi-connection parts can withstand stress that was conventionally divided. Several connections are provided.

Maximum flatness deviation B at the base of the recess 3 (see, for example, FIG. 3) and maximum flatness deviation B1 at the top of the protrusion 4
is 0.008M.

The above proportions and dimensions are obtained using blank and worked electrical steel with a thickness of 0.5 mm. The above ratio is
It is also obtained when using a 50% nickel-iron alloy with a thickness of 0.2B, which can be used in the manufacture of pole core packs of transformers.

Whether a protrusion-forming punch is applied to the edge of the strip 14 with a truncated conical slope C or a curved surface r is mainly determined by the ductility of the metal of the strip 1. When a highly ductile material is used, numbers similar to the above ratio can be obtained regardless of whether the two-conical truncated slope C or the curved surface r is applied. When using materials with low to medium ductility, it is necessary to apply a frustoconical slope C with a small angle to obtain figures similar to the above ratios.

A spring-driven stripper pad 18 is used to remove the protrusion 4 from the die 14. The action of the pad 18 may be assisted by a spring-driven ejector 18a that projects from a hole in the protrusion-forming die 14.

The ejector 18a is used to prevent deformation of the lamination, especially when using thin metal strips l. For example, the thickness T of the metal strip 1 is 0.2
If it is less than 1 mm, the ejector 18a is used. Even when the ejector 18a is used, there is no substantial change in the maximum flatness deviation B mentioned above.

The hole 2 of the partition replate roller is formed using a hole-piercing punch having the same dimensions as the recess-forming punch 13, and the shape and dimensions of the hole 2 are similar to those of the recess except that its depth matches the thickness of the material. It is equivalent to those of 3. The protrusion 4 of the lowest lamination 5 engages with the hole 2 in exactly the same manner as it engages with the recess 3.

8A to 8C, the partition plate and the lamination are cut from the metal strip 1 in two steps i to V in sequence.

FIG. 8 shows - by way of example, the manufacture of the partition plates and laminations used in the pack shown in FIG. In such packs, one connection point in each lamination is located in the center of the lamination.

In Figures 8A and 8B, in the first stage.

A positioning hole 19 is located at a location away from the center of the metal plate 1 toward the image side.
′ is punched out. These holes are used to accurately position the metal IJ tab onto the die 14, as explained below. Furthermore, if part of the metal strip is used as a partition plate, the holes 2 in the partition plate are also punched out in the first step. The second stage is the idle station. In the third stage, recesses 3 and protrusions 4 are formed. The fourth stage is the idle station. In the fifth stage, the figure-eight lamination is cut from the strip.

The manufacturing steps illustrated in FIGS. 8A to 8C are the 9th
It is carried out by using a single multi-step process machine, the outline of which is illustrated in Figures A through 9D.

In FIG. 9A, the machine is equipped with a male punch assembly 26 and a hammer punch assembly 27 secured to an automatic power brace. In the machine, a metal strip 1 is tightly gripped between a punching die plate 22 and a stripper plate 21.

In a first step, two locating holes 19' are formed by means not shown in FIG. 9A. The holes 2 in the partition plate are formed in the punching die 1 as best shown in FIG. 9B.
The metal strip 1 is punched out by the punch 11 working together with the metal strip 1 . If holes need to be punched out, the punching die 1 is driven by a cam 20 operated by an electro-pneumatic device (not shown).

As mentioned above, the second stage is the idle station.

Stages 3 and 4 need to be considered together. The positioning hole 19' is the first. Second. and passes through the third stage as it is and proceeds to the fourth stage. In the fourth stage, in order to accurately position the metal strip 1, the pilot 19
is inserted into the positioning hole 19'. In that case also the metal strip 1.

It is held tightly between the stripper plate 21 and the die plate 22. In the third stage before that.

As best shown in Figure 9C.

The recess-forming punch forms a recess and causes the metal of the strip 1 to protrude beyond the truncated conical slope C1 or curved surface r of the protrusion-forming die 14, thus forming the recess 3 and the protrusion 4. - Once the protrusion 4 is formed, the stripper pad 18. and ejector 18a if provided
is operated to remove the protrusion from the punching die 14.

The stripper pad 18 is moved by the spring 18b and the ejector 18a is moved by the spring 18b.

Each is biased by a spring 18c.

In a fifth step, the lamination 5 is punched out of the strip 1 by a punch 15 working in conjunction with a die 16, as best shown in FIG. 9D. Simultaneously with the lamination pressing, the protrusion of each lamination is fitted into the corresponding recess of the adjacent lamination,
Lamination is stacked. For this purpose, a thrust rod 17 is further provided so as to pass through the punch 15.

The thrust rod 17 engages with a recess in the punched lamination. Since there is an interference at the point where the projection 4 fits into the recess 3, the pressure exerted by the punch 15 and the thrust rod 17 is opposed by a similar counterpressure. The counterpressure is developed gradually, first by the punching die 16, then by the dividing restriction blocks 23 and 24, and finally by the adjustable pressure in the restrictor tube 25.

The restriction blocks 23 and 24 are provided with openings that are slightly smaller than the lamination and partition plates 6. This limits the free passage of the pack. The openings in the block 24 allow for the gradual development of counterpressure.
It is slightly smaller than the opening of block 23. The tube 25 has two precision ground halves 25.
' and 25'' are provided, which are spaced laterally to the tube 25.

Also, the halves are pressed against each other so that the gap between the halves is reduced. The tube halves may be fitted with several sets of disk washers (Belleville Washers), for example.
They are pressed together by the spring pressure created by 28.

The lamination 5 is stacked on the partition plate 6 as shown in Figure 9D.

The transformation of the truncated conical slope or two curved surfaces of the edge of the punching die 14 can be easily changed while the two machines are installed or in operation by means of inexpensive components including suitable correction wheels.

(Effects of the invention) Consisting of laminations connected at one point. When a torsionally flexible lamination pack is used, the electrical efficiency of the electromagnetic device is increased due to the reduction in connection points, as mentioned above.

Additionally, the single point connection configuration reduces the uninsulated contact area between adjacent pole core plates and is therefore proportionately less likely to cause problems with eddy currents between the pole core plates. Become. The torsional flexibility of the pack allows the pole faces of the connected pole core packs to abut each other along the entire length of the pack.

Air gaps that can occur in multiple fixed connection packs are thus prevented. This minimizes disruption of the magnetic flux path and increases electrical efficiency. Lamination packs according to embodiments of the present invention reduce costs for equivalent electrical efficiency compared to fixed connection packs or packs using non-fixed plates. The cost reduction is due to the fact that high quality electrical steel is not required, as in packs with fixed connections, or the use of expensive assembly equipment, as in packs constructed with non-fixed plates. .

Lamination packs made according to embodiments of the invention are useful in many types of electromagnetic devices and can be used in stators, chokes, transformers, etc.

Figure 1 is a perspective view of an electromagnetic device with two lamination packs or stacks according to the present invention.

FIG. 2 is a partial cross-sectional view of one of the packs with the partition plate of FIG. 1;

FIG. 3 is a partial sectional view showing in more detail the connection form in the lamination of the pack shown in FIG. 2. FIG.

FIG. 4 is a partial cross-sectional view of one lamination showing the recesses and protrusions in more detail.

FIG. 5 is a sectional view of the partition plate.

6 is a partial cross-sectional view of the partition plate of FIG. 5. FIG.

FIG. 7 shows an embodiment of the present invention. FIG. 3 is a partial cross-sectional view illustrating how to form recesses and protrusions in lamination.

FIGS. 8A to 8C are schematic diagrams showing steps in manufacturing a lamination pack.

9A to 9D are schematic cross-sectional views of an apparatus for manufacturing lamination packs.

that's all

Claims (13)

[Claims] 1. Pack of laminations for electromagnetic devices with torsional flexibility. 2. A pack according to claim 1, wherein each adjacent lamination is connected to each other in one place. 3. A pack of laminations for electromagnetic devices,
Each lamination has a recess on one side and a protrusion on the other side on a common axis perpendicular thereto, the protrusion forming a recess in an adjacent lamination. A pack of laminations in which each lamination is connected by a protrusion. 4. In the pack, (a) the recess and protrusion of each lamination are cylindrical, and/or (b) the base of the protrusion is a curved surface, and/or (c) the base of the protrusion is a truncated conical slope. and/or (d) the edge of the recess is a curved surface, and/or (e) the depth of the recess is greater than 50% of the thickness of the lamination, and the height of the protrusion is 50% of the thickness of the lamination. larger and less than the depth of the recess, and/or (f) the depth of the recess is about 69% of the thickness of the lamination and the height of the protrusion is about 65% of the thickness of the lamination.
The pack according to claim 3, and/or the pack further comprises a partition plate. 5. A method of manufacturing a pack of laminations for electromagnetic devices, the method comprising: adjoining each lamination by protruding one protrusion on one side of the lamination into a recess on the other side of the adjacent lamination; A method of manufacturing a lamination pack comprising making a connection with a lamination. 6. By pressing the recess-forming punch against the lamination, the lamination is projected into a protrusion-forming die to form a protrusion and a recess, the die being provided with a curved or frustoconical beveled edge, and preferably having a recess. 6. The method of claim 5, wherein the protrusion is formed to have a depth of about 69% of the thickness of the lamination and the protrusion is formed to have a height of about 65% of the thickness of the lamination. 7. Apparatus for manufacturing packs of laminations for electromagnetic devices, forming on each lamination one recess on one side and one protrusion on the other side on their vertical common axis. and means for making a connection between each lamination and an adjacent lamination by projecting one protrusion on one side of the lamination into a recess on the other side of the adjacent lamination. Equipment for manufacturing lamination packs for equipment. 8. 8. Apparatus according to claim 7, wherein the forming means comprises a protrusion forming die having a curved or conical sloped edge, and means for pushing the protrusion beyond the edge into the die. . 9. A lamination for an electromagnetic device, with a recess on one side of the lamination and a protrusion on the other side on a common axis perpendicular to the lamination, the protrusion A lamination having a structure such that the lamination is connected to an adjacent lamination only by protruding into the one recess of the adjacent lamination. 10. In the lamination, (a) the recess and the protrusion are cylindrical, and/or (b) the base of the protrusion is a curved surface, and/or (c)
the base of the protrusion is a truncated conical slope, and/or (d) the edge of the recess is a curved surface, and/or (e) the depth of the recess is greater than 50% of the thickness of the lamination, and the height of the protrusion is (f) the depth of the recess is approximately 69% of the thickness of the lamination and the height of the protrusion is greater than 50% of the thickness of the lamination and less than the depth of the recess; Approximately 65% of lamination thickness
The lamination according to claim 9. 11. A method of forming protrusions and/or recesses in a sheet of ductile material by pressing a punch into the material and protruding into the die beyond the edge of the curved surface or frustoconical slope of the protrusion-forming die. A method of forming protrusions and/or recesses in a sheet of ductile material comprising extruding the parts. 12. 12. The method of claim 11, wherein the height of the protrusion and/or the depth of the recess is about 65% to about 70% of the thickness of the material. 13. An electromagnetic device comprising a lamination pack according to any one of claims 1 to 4.