EP1597739B1 - Insulating element, toroidal core, toroidal core choke, and method for producing said toroidal core choke - Google Patents

Description

The invention relates to an insulating part for installation in the interior of a toroidal core. Furthermore, the invention relates to a toroidal core with an insulating part. Moreover, the invention relates to a toroidal core choke. Moreover, the invention relates to a method for winding a toroidal core.

To produce multiple inductors, a plurality of mutually insulated windings are applied to toroidal cores along a circumference. In order to ensure the electrical insulation between the windings, one or more potential separations are provided in the interior of the toroidal core. As a result, the winding space located in the interior of the toroidal core is preferably subdivided into several equally sized winding spaces.

Since the toroidal cores are sintered during manufacture with insulation, the sintered cores have relatively large deviations from one another with respect to their inner diameter. A potential separation should be able to compensate for these tolerances as much as possible.

It is known to set up the toroidal core on a holder with molded insulating bars. This has the disadvantage that the potential separation can be installed only after winding. Therefore remains in chokes with a large number of turns, which must be arranged in two or even more layers on the toroidal, no or very little space for retrofitting the molded Isolierstege.

Furthermore, it is known to insert two Preßspanplättchen each other and then install in the ring core. This has the disadvantage that the platelets during winding can be easily moved by the winding tension. This would mean that the changing rooms would differ in size from each other. As a result, it would not be possible to arrange a plurality of equal-sized windings on the throttle under optimum utilization of the available space.

According to another known technique for producing the potential separation, a plurality of plastic platelets are clamped against one another in the core hole, that is, in the interior of the ring core. This has the disadvantage that the arrangement of plastic platelets is really stable only after the installation of the last platelet. In addition, this has the disadvantage that a relatively high effort is required for installation.

From the publication EP 0 258 592 A is Isolierteil for installation in the Kernloch.eines a ring core with radially extending webs known. The insulating part consists of a plastic with elastic properties.

It is also known to use toroidal cores in plastic troughs or cores coated with plastic with integrally formed grooves for receiving rigid Kunststoffisolierstegen or Kunststoffisolierkreuzen. The plastic casing accommodates the tolerances of the inner core diameter. Such an arrangement has the disadvantage that is lost by the plastic wrapping valuable changing room. Furthermore, there is the disadvantage that the envelope is costly to manufacture because of its complex geometric shape.

It is therefore an object of the present invention to provide an insulating part for a toroidal core, which can be easily assembled and can compensate for the tolerances of core hole diameters.

This object is achieved by an insulating part according to claim 1. In the further claims advantageous embodiments of the insulating part, a toroidal core for a toroidal core choke, a toroidal core choke and a method for winding a toroidal core are given.

An insulating part for installation in the core hole of a toroidal core is shown, which contains a number n ≥ 2 radially outwardly extending webs. In this case, at least one web on an elastically deformable spring element in the form of elastic tongues, which are arranged at the outer end of the web. The elastic tongues may be arranged, for example, for one or more webs in pairs at their outer ends and in each case deviate from the radial direction.

The insulating part has the advantage that it can be adapted to different core hole diameter of toroidal cores due to the preferably deformable by a radial force spring element. In addition, the insulating part has the advantage that it can be easily and inexpensively, for example, produced by injection molding due to its simple structure.

In an advantageous embodiment of the insulating part adjacent webs may be interconnected by elastic support members. These support elements can be used simultaneously for isolating the core hole into winding spaces. They form, for example, complementary to the lying between two webs portion of the ring core an inner boundary.

In another embodiment of the insulating part, the webs are offset substantially by an angle of 360 ° / n against each other. This makes it easy and advantageous to divide the core hole in the same size changing room.

In another embodiment of the insulating part, this has an n-fold symmetry axis. By this is meant that the insulating part upon rotation about the axis of symmetry is imaged on itself at an angle of 360 ° / n. Such a symmetry has the advantage that the production can be substantially simplified, since the smallest possible variety of shapes is observed.

In another embodiment, the insulating part is integrally formed. As a result, it can be produced, for example, advantageously by an injection molding technique.

In another embodiment of the insulating part, this may be a thermoplastic, for. As polycarbonate. The material polycarbonate has the advantage that it is very well insulated on the one hand electrically and on the other hand has a very good fire behavior, namely a very low flammability according to the standard UL 94 V-0.

As polycarbonate, for example, the materials Lexan or Macrolon come into consideration.

In addition, a ring core is specified, which contains one of the insulating parts just described in its core hole. Such a toroidal core has the advantage that it can be used very advantageously for producing a toroidal core choke. Such a production method is given below:

It is used a toroidal core, in the core hole an insulating part is arranged. The insulating part is formed so that it projects beyond the ring core in the axial direction. The insulating part can protrude on the top and on the bottom of the toroidal core or even on one side. During the winding of the toroidal core this is held on the insulating part. This approach has the advantage that the mechanically very sensitive and, for example, sintered annular core is not mechanically stressed during winding by a holding device.

In addition, a toroidal choke is specified, which contains a toroid just described. In addition, each lying between two webs portion of the toroidal core is wound with a winding.

By such a toroidal core choke can be in a simple manner, a multiple throttle with a plurality of mutually insulated windings, which may also contain the same number of turns realize.

Figur 1

zeigt ein beispielhaftes Isolierteil in einer Draufsicht.

Figur 2

zeigt das Isolierteil aus Figur 1 in einer Seitenansicht.

Figur 3

zeigt eine beispielhafte Ringkerndrossel enthaltend ein Isolierteil nach Figur 1 in einer Seitenansicht.

Figur 4

zeigt die Ringkerndrossel aus Figur 3 in einer Draufsicht.

In the following the invention will be explained in more detail by means of exemplary embodiments and the associated figures:

FIG. 1

shows an exemplary insulating part in a plan view.

FIG. 2

shows the insulating part of Figure 1 in a side view.

FIG. 3

shows an exemplary toroidal core choke containing an insulating part of Figure 1 in a side view.

FIG. 4

shows the toroidal core choke of Figure 3 in a plan view.

It should be noted that elements denoted by like reference numerals are the same or at least the same in function.

FIG. 1 shows an insulating part 1 in a plan view. It has webs 31, 32, 33, which are interconnected by carrier elements 421, 422, 423. The webs 31, 32, 33 extend in the radial direction away from an imaginary center of the insulating part. Through the imaginary center of the insulating part 1 runs the axis of symmetry 5 (see Figure 2).

The support elements 421, 422, 423 are designed very thin-walled and have a relatively large outer or inner radius of curvature R1, R2. For example, the inner radius of curvature R1 may be 16.5 mm and the outer radius of curvature R2 may be 16 mm. This results in a wall thickness of the support elements of 0.5 mm. Such support members 421, 422, 423 are characterized by a high elasticity, which means that they can be deformed in the radial direction by pressing the rigid compared to the support members webs 31, 32, 33, and thus the adaptability of the insulating part to different core hole diameter demonstrate.

The webs 31, 32, 33 have a wall thickness W of 2 mm. The support elements 421, 422, 423 have a wall thickness w of 0.5 mm.

At the outer ends of the webs 31, 32, 33 are pairs of tongues 411a, 411b; 412a, 412b and 413a, 413b. These tongues extend in a direction deviating from the radial direction and are designed in terms of their wall thickness so that they equal the wall thickness of the support elements 421, 422, 423. The tongues 411a, 411b, 412a, 412b, 413a, 413b in this case fulfill the function of the spring elements 4. By exerting a pressure in the radial direction, the tongues and the carrier elements of the insulating part can be bent to the side, and an adaptation of the insulating part to smaller core hole diameters can take place.

The insulating part 1 has in its center a roughly triangular, straight through the entire height (see Figure 2) running cavity, whereby the insulating part 1 can be very easily produced by injection molding. Due to the support elements 421, 422, 423, each connecting two webs 31, 32, 33, the insulating part also has a high mechanical stability, which allows to insert the insulating part as a one-piece element before winding the ring core in the core hole ,

In the case of three webs 31, 32, 33, these are offset by an angle α of 120 ° from each other.

It should be noted, however, that the present invention is not limited to three lands. Rather, it is contemplated to use instead of three and two or four or five or a larger integer number of webs to divide the core hole of the toroidal in the same size or simply in a variety of changing rooms.

It is indicated in Figure 1 that the insulating member extends radially so far that it can be circumscribed by a circle with a diameter D of 32.4 mm.

The center of the circumscribing circle also forms the center of the insulating part, which is to be considered in each case with the term "radial".

Due to the cooperating with the rigid webs spring elements 4, which are included in the insulating part of Figure 1, the insulating part can be very mechanically fixed in the core hole of a toroidal core, which has the advantage that the webs of the insulating member 1 does not push away during the winding to let.

For the purpose of production by injection molding a pressing surface 12 is still provided, by means of which the insulating part 1 can be pushed out of the injection mold.

Figure 2 shows a side view of the insulating part 1 of Figure 1, from which the height h of 24 mm emerges. In addition, in Figure 2, the axis of symmetry 5 is shown, which runs through the center of the insulating part 1, shown in Figure 1 as the center of the outer circle. From Figure 2 also shows that 1 bevels 13 may be provided on the sides at the top and on the underside of the insulating part can, in which the outer edges are inclined relative to the axis of symmetry 5 by an angle β. The angle β can be for example 45 °. The chamfers 13 facilitate the insertion of the insulating part in the core hole of a toroidal core, since thus an automatic self-centering is achieved.

FIG. 3 shows a toroidal core choke in a side view. It is shown a toroidal core 2, on which a winding 8 is applied. In the core hole of the toroidal core 2, an insulating part 1 is inserted according to FIG. The height h of the insulating part 1, and the height hR of the toroidal core and the height hW of the winding 8 are chosen so that on both sides, ie on the upper and on the lower side of the toroidal core 2, a projection 7 of the insulating 1 results. This projection 7 may be present on one or both sides of the ring core. It is used to hold the toroidal core 2 during the winding of the windings 8.

FIG. 4 shows a plan view of the toroidal core choke from FIG. 3. It can be seen that the core hole 6 is divided by the insulating part 1 into three equally large winding spaces 111, 112, 113. Each lying between two webs portion 91, 92, 93 of the toroidal core 2 is wound with a wire 10, whereby three mutually well insulated windings 8 have arisen.

It should be noted that the present invention is not limited to the embodiments shown here. It is rather conceivable that instead of three, fewer or more webs are used to divide the core hole into changing rooms.

LIST OF REFERENCE NUMBERS

1

Insulation

2

toroidal

31, 32, 33

web

4

spring element

411a, 411b, 412a, 412b, 413a, 413b

tongue

421, 422, 423

support element

5

axis of symmetry

6

core hole

7

Got over

8th

winding

91, 92, 93

section

10

wire

111, 112, 113

changing room

12

pressing surface

13

bevel

α, β

angle

D

diameter

W

Wall thickness

w

Wall thickness

h, hR, hW

height

Claims (10)

1. Insulating element for fitting into the core hole of a toroidal core (2) containing a number n ≥ 2 of webs (31, 32, 33) running radially outwards, at least one web (31, 32, 33) having an elastically deformable spring element (4), characterized in that elastic tongues (411a, 411b, 412a, 412b, 413a, 413b) are arranged at the end of a web (31, 3-2, 33).
2. Insulating element according to Claim 1, in which two adjacent webs (31, 32, 33) are joined together by elastic support elements (421, 422, 423).
3. Insulating element according to one of Claims 1 to 2, in which the webs (31, 32, 33) are essentially offset from one another by an angle (α) of 360°/n.
4. Insulating element according to one of Claims 1 to 3, which has an n-fold axis of symmetry (5).
5. Insulating element according to one of Claims 1 to 4, which is made in one piece.
6. Insulating element according to one of Claims 1 to 5, which is an injection-moulded element.
7. Insulating element according to one of Claims 1 to 6, which contains a thermoplastic.
8. Toroidal core containing an insulating element (1) according to one of Claims 1 to 7 in its core hole (6) .
9. Method for winding a toroidal core (2),

   - wherein a toroidal core (2) according to Claim 8 is used, in which the insulating element (1) extends in an axial direction,

   - and wherein the toroidal core (2) is held by the insulating element (1) while it is being wound.
10. Toroidal core choke containing a toroidal core (2) according to Claim 8, in which each section (91, 92, 93) of the toroidal core (2), which lies between two webs (31, 32, 33), is wound with a winding (8).

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