EP1846933B1 - Insulation element and toroidal core throttle - Google Patents

Description

The invention relates to an insulating part for potential separation of a toroidal core choke with several windings. Moreover, the invention relates to a toroidal core choke with an insulating part.

An insertable into a toroidal insulator for a toroidal core choke according to the preamble of claim 1 is made DE 103 08 010 A1 known. Out DE 33 18 557 A1 Another insulating part with a spreading is known.

Object of the present invention is to provide an insulating part for a toroidal core choke, which is also used in small toroidal cores and allows a spatial separation of the windings of a toroidal core choke from each other.

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

There is provided an insulating member for incorporation into the core hole of a toroidal core having a separator for forming separate winding spaces and interconnecting spacers. The separating device comprises at least one separating web extending in a radial direction and connected at its first end to a first spacer, whose width W is smaller than the width b of this spacer.

When installed, the width b of the spacer is large against the width W of the divider.

The width W is understood in accordance with a preferred variant of the insulating part as the thickness of a separating web or its cross-sectional width. The divider is preferably solid and has no voids.

At least one of the spacers constitutes an elastically deformable expansion part. The elastically deformable expansion part has, in the deformed state transversely to the radial direction and to a longitudinal direction of the insulating part, a width that is large compared to the width W of the separating web. The elastically deformable expansion part is deformable under the action of a force acting in the radial direction, whereby its width measured transversely to the radial direction increases. Due to the fact that the deformable expansion part under the action of the force usually against a support -. B. the inner wall of a toroidal - supports, the dimensional stability of the deformable expansion member can be achieved with respect to its width transversely to the radial direction, so that it is transverse to the radial direction as a spacer z. B. is used for the spatial separation of two windings of a toroidal core choke. The width of the deformable expansion part thus determines the isolation distance of the insulating core comprehensive toroidal core choke. The width of the deformable expansion part is z. B. at least 2 x W.

The radially extending divider, whose width is indicated for example by W, has at its first end an elastically deformable expansion part. The expansion part has in the spread state, a spread b - d. H. a clear distance between Spreizendpunkten - on, which is preferably at least twice the width W. In an advantageous variant, b ≥ 3W.

The width W of the divider is preferably chosen so that the divider is indeed relatively narrow, but still rigid.

The wall thickness w of components of the expansion part is preferably chosen in contrast so that these components are at least partially deformable, for. B. flexible and thus are spreadable.

The measured in the radial direction length h of the expansion in the spread state is preferably low against its spread b, in a variant h <0.4b.

The radial length h of the expansion part in the spread state is preferably small compared with the length a of the separating web measured in the radial direction, in one variant h <0.5a, in a preferred variant h <0.4a.

The radial length h of the expansion part in the spread state is preferably small relative to the-defined by the diameter of the core hole-cross-sectional size d of the insulating part, in a variant h <0.2d.

The spreader is pressed during installation in a toroidal core at Spreizendpunkten against the inner wall of the toroidal core. In this case, the slippage of windings to be separated from one another beyond the expansion end points is prevented and thus a predetermined isolation distance is ensured between the expansion end points, that is to say essentially transversely to the radial direction or also in the circumferential direction of the ring core. The expansion part therefore serves as a spacer between separable windings. The isolation distance is determined by the clear distance L between Spreizendpunkten and is substantially equal to this distance.

Characterized in that spacer elements are formed to secure an insulation distance in a space-saving manner at the end of the web, the divider can be made particularly narrow. Thus, relatively large, separate baby changing rooms be ensured despite compliance with a large isolation distance.

Since the insulating is resilient by the expansion in the radial direction, a simple assembly when installed in a toroidal core is possible. Although the ring cores can have relatively large deviations from one another with respect to their inner diameter, it is possible to compensate for these tolerances with the specified insulating part.

The divider is preferably Y-shaped in cross-section, d. H. branched to form a cross-sectionally V-shaped expansion part at its first end in two spring elements. In this case, the expansion part has two elastically deformable, preferably leaf-shaped, spring elements (bending spring), which differ in cross-section from a radial direction. The cross-sectional length L of a spring element measured transversely to the separating web main surface is large relative to the width W of the separating web, e.g. B. L> 1.5W, preferably L> 2W.

The spread angle β can be, for example, between 90 ° and 180 °, preferably between 120 ° and 170 °. With a large spread angle ≥ 150 °, it is possible to achieve a particularly large spread width and therefore a particularly large insulation distance and the largest possible winding spaces.

The cross-sectional length L of a spring element is preferably large compared to the radial length h of the expansion, z. B. L> 2h. The cross-sectional length L of a spring element may in one variant be more than 0.5a, where a is the radial length of the separating web.

The width W of the divider becomes dependent on elastic properties of the material of the divider and on the diameter the core hole chosen so that the separation bar is indeed thin, but remains dimensionally stable when inserted into the core hole. The width W of the divider is preferably between 1.5 and 5 mm, z. 1 to 1.5 mm with a core hole diameter below 15 mm, 1.5 to 2 mm with a core hole diameter between 15 and 25 mm, 1.5 to 2.5 mm with a core hole diameter between 20 and 50 mm and 2, 5 to 5 mm with a core hole diameter between 50 and 100 mm. The wall thickness w of a spring element - apart from its regions with bevelled edges - is preferably at least 50% of the width W of the separating web.

The cross-sectional length L of the respective spring element is preferably at least 3.5 mm. The cross-sectional length L of a spring element can be at least 4.5 mm in one variant.

The spread width b of the expansion part can be greater than 8 mm in one variant and greater than 9 mm in a preferred variant.

Advantageously, a device serving as an abutment can be provided at the second end of the separating web. The abutment can be formed in a variant by a further expansion part, which also serves as a spacer to ensure the predetermined insulation distance and is preferably formed as the first expansion part. Such an insulating part is suitable for a toroidal core choke with two windings.

In a further variant, the abutment by a z. B. dimensionally stable part, which is a widened part of the divider and serves as a spacer to ensure the predetermined isolation distance. This insulating part can be used in particular in a toroidal core choke with two windings.

In a variant, the major surfaces of the widened part at an angle between 60 ° and 120 °, z. B. 80 ° to each other. The widened part of the separating web can have the basic shape of a circular sector in cross section. The side facing away from the divider edge of the widened portion of the divider can have the shape of a circular arc in cross section, whose length z. B. is at least 10 mm. The widened part may also have bevelled edges and / or at least one recess for receiving a holding element.

In a further variant, the abutment may be formed in that the separating web is connected at its end facing away from the spreader end, which forms a star point, star-shaped with further preferably identically designed separating webs. The further separating webs preferably also each have a spreading part at its end remote from the star point. A number n ≥ 2 of separating webs is used for isolating the core hole into n winding spaces. It is expedient to form all expansion parts of the insulating part similar. In one 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.

Thus, in an advantageous variant, the insulating part can have a plurality of radially extending separating webs with two elastically deformable spring elements extending deviating from a radial direction. It is expedient to form the spring elements connected to the same separation bridge symmetrical to each other. It is advantageous to design different dividers with the spring elements similar.

The insulating part is preferably formed in one piece. The insulating part is preferably an injection molded part, which in a variant a thermoplastic, for. B. contains polycarbonate. Polycarbonate has the advantage that on the one hand it is electrically very well isolated and on the other hand it has a very good fire behavior, namely only very low flammability in accordance with the standard UL 94 V-0. As polycarbonate, for example, the materials Lexan or Macrolon come into consideration. There are also other electrically insulating materials in question, which are dimensionally stable and deformable in a smaller, provided for spring elements strength in a given thickness for the divider.

The insulating part is characterized by a high mechanical stability, which allows to insert the insulating part as a one-piece element before winding the toroidal core in the core hole. Each section of the toroidal core lying between two separating webs is wound with a winding. Thus, a toroidal core choke is provided with a potential separation.

Due to the cooperating with the rigid dividers spring elements, 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 can not push away during the winding.

With the specified insulating succeeds, a large insulating distance, d. H. To achieve air and creepage distance between two windings to be separated without restricting the winding space defined by the core hole.

In an advantageous embodiment of the insulating part, this has an n-fold symmetry axis. By this is to be understood that the insulating part is mapped on rotation about the axis of symmetry by an angle of 360 ° / n on itself. Such symmetry has the advantage that the production is essential can be simplified, since the smallest possible variety of shapes is observed.

• Figur 1 eine Draufsicht auf ein Isolierteil zur Trennung von zwei Wicklungen;
• Figur 2A die Projektion des Isolierteils gemäß Figur 1 auf die Projektionsebene BB';
• Figur 2B die Draufsicht auf die Hauptfläche des Isolierteils gemäß Figur 1;
• Figur 2C ein Federelement im Querschnitt durch die Querschnittsebene AA';
• Figur 2D eine Ansicht des Isolierteils gemäß Figur 1 von unten;
• Figur 2E eine Ansicht des Isolierteils gemäß Figur 1 von oben;
• Figur 3 eine Draufsicht auf ein weiteres Isolierteil zur Trennung von zwei Wicklungen;
• Figur 4 eine Draufsicht auf ein Isolierteil zur Trennung von drei Wicklungen;
• Figur 5 eine Draufsicht auf ein Isolierteil zur Trennung von vier Wicklungen;
• Figur 6 das Isolierteil gemäß Figur 1 in einer perspektivischen Ansicht;
• Figur 7 eine perspektivische Ansicht einer Ringkerndrossel mit dem Isolierteil gemäß Figur 1.
• Figur 8 Querschnitt der Ringkerndrossel gemäß Figur 7.

In the following the invention will be explained in more detail with reference to embodiments and the accompanying figures. The figures show diagrammatic and not true to scale representations of various embodiments of the invention. Identical or equivalent parts sind.mit same reference numerals. It show schematically

• FIG. 1 a plan view of an insulating part for the separation of two windings;
• FIG. 2A the projection of the insulating part according to FIG. 1 on the projection plane BB ';
• FIG. 2B the top view of the main surface of the insulating part according to FIG. 1 ;
• Figure 2C a spring element in cross-section through the cross-sectional plane AA ';
• FIG. 2D a view of the insulating part according to FIG. 1 from underneath;
• Figure 2E a view of the insulating part according to FIG. 1 from above;
• FIG. 3 a plan view of another insulating part for the separation of two windings;
• FIG. 4 a plan view of an insulating part for the separation of three windings;
• FIG. 5 a plan view of an insulating part for the separation of four windings;
• FIG. 6 the insulating part according to FIG. 1 in a perspective view;
• FIG. 7 a perspective view of a toroidal core choke with the insulating part according to FIG. 1 ,
• FIG. 8 Cross section of the toroidal core choke according to FIG. 7 ,

In FIGS. 1, 2A to 2E and 6 different views of an insulating part according to a first embodiment are presented.

FIG. 1 shows a plan view of an end face of the insulating part, ie on a transversely to the main surface of its divider 11 extending side of the insulating part.

The radially extending separating web 11 is branched at its upper (first) end to form leaf-shaped spring elements 111, 112 in this example. The pairs arranged at the outer end of the divider spring elements 111, 112 each differ from the radial direction.

The spring elements 111, 112 together form a first expansion part 102, which is suitable as a spacer for maintaining an insulation distance. The spring elements 111, 112 form in the ground state - ie before insertion into the core hole of a toroidal - an angle of z. B. 120 ° to 170 ° to each other and when inserting into the core hole ( Fig. 7 ) further spread, pressing against the inner wall of the toroidal core 2.

By exerting a pressure in the radial direction, the spring elements of the insulating part can be deformed. The spring elements 111, 112 are characterized by their flexibility, which means that they by pressing the compared with the spring elements rigid web 11 can be bent in the radial direction to the side, so that the insulating part can be adapted to different core hole diameter.

The separating web 11 has at its lower (second) end a widened part 10, which has the basic shape of a circle segment in cross-section transverse to the main surface of the separating web. The common part 10 forms a second spacer for maintaining an insulation distance.

The widespread part 10 has two recesses 100, each for receiving a holding element 5 (FIG. Fig. 7 ) are suitable.

The main surface 110 of the divider 11 is parallel to an in Figures 2B, 2D and 2E shown longitudinal axis C, along the axial direction of a in FIG. 7 shown ring core 2, in which the insulating part is used, is directed.

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 expansion part. In addition, the insulating part has the advantage that it can be made simply and inexpensively, for example by injection molding due to its simple structure.

In FIG. 2A is a view of the insulating part according to FIG. 1 from the perspective of the plane BB 'and in FIG. 2B a side view of the insulating part shown.

In Figure 2C the spring element 111 is shown in a schematic cross section through the plane AA '.

The spring element 111 has chamfered edges 91, 92 ( Fig. 2C and 2E ). The maximum wall thickness w of the spring element 111 is at least half of the separating web width W. This applies equally to the second spring element 112.

The widened part 10 may have chamfered edges 93, 94 ( Fig. 2B and 2D ). In principle, all edges and / or joints - z. B. the joint of the divider 11 and the part 10 or the joint of the divider 11 and the spring element 111 and 112 - be rounded. The provided on the insulating chamfers 91 to 94 facilitate the insertion of the insulating part in the core hole of a toroidal core.

On the one hand by the spring elements 111, 112 and on the other hand by the widened part 10 succeeds at both ends of the insulating part, the windings 31, 32 of the toroidal core choke apart and thus maintain the required minimum distance (isolation distance) between the windings. The isolation distance can z. B. 9.6 mm (air gap) amount, which corresponds to a measured along the inner wall of the toroidal creepage distance of 12.7 mm.

In FIGS. 3 to 5 Further possible embodiments of an insulating part with n separating webs for potential separation between n windings are shown. The insulating part has an n-fold symmetry axis in the embodiments shown here. The symmetry axis is transverse to the plane of the figures.

The webs 11 and 12 (as well as web 13 in Fig. 4, 5 and jetty 14 in Fig. 5 ) extend in the radial direction away from an imaginary center of the insulating part. Through the imaginary center of the insulating part runs not shown in figures n-fold symmetry axis.

In FIG. 3 an insulating part for the separation of two windings is shown (n = 2). The divider 11 has at both ends each one spreader 102 and 102 'on. Both spreading parts are the same. The expansion part 102 comprises two spring elements 111, 112 and the expansion part 102 'two spring elements 111', 112 '.

The spring element 111 has a length L11 = L and the spring element preferably has the same spring length L12. The spread width b is at equal length spring elements 2L x sin (β / 2), where L is the cross-sectional length of a spring element and β is a spread angle. The radial length h of the expansion part is approximately h = w + L x cos (β / 2), where w is the wall thickness of the spring element.

The dividers 11, 12, 13, 14 at n> 2 are connected to each other in a star shape (see FIGS. 4 and 5 ).

A separator 1 of the insulating part is in FIGS. 1 . 3 and 6 formed by the divider 11. In FIG. 4 the separating device comprises three at a virtual center star-shaped interconnected partitions 11, 12, 13 and in FIG. 5 four interconnected dividers 11, 12, 13, 14th

In FIG. 4 an insulation part for the separation of three windings is shown (n = 3). The angle between two separating webs 11 and 12, 12 and 13 and 13 and 11 is here 360 ° / n = 120 °.

The separating web 12 is branched at its outwardly pointing end into spring elements 121, 122 and the separating web 13 into spring elements 131, 132. All dividers here have the same length a.

The radial length h of the expansion element formed by the spring elements 111, 112 is substantially smaller than the web length a, da the spread angle β is chosen to be large. For this reason, the spread width b (see Fig. 3 ) extraordinary big.

In FIG. 5 an insulation part for the separation of four windings is shown (n = 4). The angle between two separating webs 11 and 12, 12 and 13, 13 and 14 and 14 and 11 is here 360 ° / n = 90 °.

An asymmetrical insulating part with n dividers is also possible. An insulating part with n> 4 dividers for the formation of n separate winding spaces is also provided.

In FIG. 7 is an exemplary toroidal core choke with an insulating part according to the embodiment of FIG. 1 shown. The toroidal core choke comprises a toroidal core 2 with a core hole and two windings 31, 32. The core hole is divided by the insulating part 11, 111, 112, 10 into two separate winding spaces for accommodating a winding 31 and 32, respectively. Due to the fact that the divider 11 with z. B. 1.5 to 3 mm is relatively narrow, comparatively large changing rooms are provided.

The toroidal core choke is mounted on a mounting plate 4, are provided in the openings for receiving coil ends to comply with a predetermined pitch of the toroidal core choke. On the mounting plate, two holding elements 5 are preferably provided for vertical fixing of the toroidal core choke, wherein in FIG. 7 only one holding element 5 is visible. The holding element 5 fits positively into the recess 100 of the insulating part. The holding element 5 holds the throttle in the in FIG. 7 presented variant not on the insulating part, but at the toroidal core.

The length of the separating web 11 measured in the radial direction is preferably at least 50% of the diameter of the core hole. In one variant, the length of the separating web 11 is at least 70% of the diameter of the core hole.

The cross section of the toroidal core choke through the sectional plane DD 'is in FIG. 8 shown.

In the axial direction (longitudinal direction C, see Fig. 2B, 2D, 2E ) measured height of the insulating part is preferably greater than the height of the toroidal core 2, so that the insulating part in this direction beyond the toroidal core z. B. on both sides, see FIG. 8 , This is advantageous for fixing the arrangement of the core and the insulating part in the component winding of the core. A protruding insulating part is also suitable by the supernatant of the separating web 11 to extend a so-called creepage and clearance, even with a tightly wound throttle a predetermined clearance and creepage distance can be ensured even in the central region of the throttle.

In an advantageous variant, the separating web 11 of the insulating part is in the axial direction on both sides at least 3 mm each over the ring core 2 or over the (in Fig. 8 upper or lower) edge of the throttle. The respective supernatant is in a preferred variant at least 4.5 mm.

The actual clearance and creepage distance is the sum S = 11 + W + 12 of the cross-sectional size of the separating web W, a distance 11 between the - in FIG. 8 facing down - front side of the divider 11 and the terminal, turned to the divider turn of the first winding 31, and a distance 12 between the end face of the divider 11 and the terminal, turned to the divider turn of the second winding 32 together. The actual clearance and creepage distance is preferably at least as great as the predetermined clearance and creepage distance.

The fact that the actual air and creepage distance is de facto extended by means of a protruding insulating part, it is possible, on the one hand to comply with the predetermined larger air and creepage distance and on the other hand to exploit the existing winding space, which is an important advantage, especially in ring cores with a small inner diameter.
The windings 31, 32 are in a radial direction, which in FIG. 7 extends transversely to the divider, spaced by the distance d from each other. In a preferred, also in FIG. 8 shown variant, this distance is smaller than the actual creepage distance and creepage distance S = 11 + W + 12. A sufficient clearance and creepage distance is thus ensured by means of a projecting beyond the ring core separating web 11 of the insulating part in the central region of the throttle, said Distance d smaller than the specified clearance and creepage distance may be selected.

The invention is not limited to the number of elements shown in figures. The formation of a spreader is not limited to leaf-shaped spring elements. Rather, all possible suitable devices are considered in order to achieve a suspension of the preferably rigid webs in the radial direction. The webs can be executed both solid and as a hollow profile.

LIST OF REFERENCE NUMBERS

1

separating device

10

Broadening of the divider 11

100

deepening

102

first spacer

102 '

second spacer

11, 12, 13

divider

110

Main surface of the separating web 11

111, 112

deformable spring elements of the separating web 11

121, 122

deformable spring elements of the separating web 12

131, 132

deformable spring elements of the separating web 13

31, 32

windings

4

mounting plate

5

retaining element

91, 92

beveled edges of the spring element 111

93, 94

beveled edges of the part 10

AA '

Cross-sectional plane

BB '

projection plane

a

radial length of the divider

b

Spreading width of the expansion part 102

d

radial distance between opposing windings

C

longitudinal axis

H

Length of the spreader

l1, l2

Distance between terminal winding and front side of the divider

L10

Length of the secants of the arc

L11

Length of the spring element 111

L12

Length of the spring element 112

w

Wall thickness of the deformable spring element

W

Width of the divider 11

Claims (19)

1. Insulating part for fitting into the core hole of a toroidal core (2), comprising a separating device (1) for forming separate winding spaces and for connecting spacers (102, 10; 102, 102'),

   - wherein the separating device (1) has at least one divider (11),

   - wherein a first spacer (102), which is formed as an elastically deformable spreading part (102), is arranged at a first end of the divider (11), and

   - wherein the elastically deformable spreading part (102) has in the spread-open state transversely in relation to the radial direction a spread width b,
   characterized

   - in that the spread width b is greater than the width W of the divider (11).
2. Insulating part according to Claim 1, wherein b ≥ 2W.
3. Insulating part according to Claim 2, wherein the radial length h of the spreading part (102) in the spread-open state is less than the spread width b.
4. Insulating part according to Claim 3, wherein h ≤ 0.4b.
5. Insulating part according to either of Claims 3 and 4, wherein the radial length h of the spreading part (102) in the spread-open state is small in comparison with the radial length a of the divider (11), wherein h ≤ 0.5a.
6. Insulating part according to one of Claims 1 to 5, wherein the spreading part (102) has at its first end two elastically deformable spring elements (111, 112), running divergent from a radial direction.
7. Insulating part according to Claim 6, wherein the divider (11) is Y-shaped to form spring elements (111, 112).
8. Insulating part according to one of Claims 1 to 7, wherein the divider (11) has at a second end a second spacer, to be specific a widened part (10), which serves during the insertion into a core hole as an abutment for the first spacer (102).
9. Insulating part according to Claim 8, wherein the main surfaces of the widened part (10) form in relation to one another an angle of between 60° and 120°.
10. Insulating part according to one of Claims 1 to 7, wherein the divider (11) has at a second end a further spacer (102').
11. Insulating part according to one of Claims 1 to 7, wherein the separating device (1) comprises more than just one radially running divider (11, 12, 13) with in each case a spacer (102, 102'), wherein the ends of different dividers (11, 12, 13) that are remote from spacers (102, 102') are connected to one another in a star-shaped manner.
12. Insulating part according to Claim 11, wherein the separating device (1) has a number n ≥ 2 of dividers (11, 12, 13, 14), wherein the dividers (11, 12, 13, 14) are offset from one another substantially by an angle (α) of 360°/n.
13. Insulating part according to one of Claims 1 to 12, which is formed as one piece.
14. Insulating part according to one of Claims 1 to 13, which is an injection-moulded part.
15. Insulating part according to one of Claims 1 to 14, which comprises a thermoplastic.
16. Toroidal-core inductor with a toroidal core (2) and with an insulating part according to one of Claims 1 to 15 in the core hole of the toroidal core (2).
17. Toroidal-core inductor according to Claim 16, wherein each portion of the toroidal core (2) lying between two dividers (11, 12, 13) is wound with a winding (31, 32).
18. Toroidal-core inductor according to Claim 16 or 17, wherein the divider (11) of the insulating part projects beyond the toroidal core (2) on both sides in the axial direction.
19. Toroidal-core inductor according to Claim 18, wherein the respective projection is at least 3 mm.

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