EP2801987A1 - Inductive component - Google Patents

Abstract

Inductive component (1) with at least one winding (2.1, 2.2), wherein the winding (2.1, 2.2) via a thermally conductive insulator (4.1, 4.2) with a cooling element (3) is heat-coupled. According to the invention, it is provided that the insulator (4.1, 4.2) has the at least one winding (2.1, 2.2) surrounding it in a surface-locking manner, and the cooling element as the housing (3) receiving at least one winding (2.1, 2.2) with an interior space (3.11, 3.12, 3.21, 3.22) is formed, wherein the inner contour of the interior (3.11, 3.12, 3.21, 3.22) of the housing (3) of the outer contour of the insulator (4.1, 4.2) is adjusted.

Description

The invention relates to an inductive component having at least one winding according to the preamble of patent claim 1.

Such an inductive component is designed as a throttle with a arranged on a magnetizable magnetic core winding, for example, from the DE 10 2011 082 045 A1 generic known. For efficient cooling of this known throttle, a flat cooling element is provided which is thermally coupled to the surface of the winding facing away from the magnetic core and for this purpose, a heat-conducting electrical insulator in the form of an electrically insulating heat-conducting foil is provided between this cooling element and the winding. Since the winding has a rectangular cross-section as a single-layer winding, this heat-conducting foil rests on a flat surface of this rectangular shape of the winding and is covered by the plane cooling element in a surface-locking manner.

Furthermore, from the EP 1 501 106 B1 a choke with a segmented magnetic core is known, which can be provided with a heat sink in order to realize the highest possible power density. Both the winding and the magnetic core of this known throttle provides enough "attack surface" for a passive heat sink.

Furthermore, the describes EP 1 772 877 B1 an inductive component in which flexible insulating films, in which heat-conductive ceramic or quartz powder-containing fillers are incorporated, are provided. However, there is only provided there to arrange the heat sheets between the primary and secondary windings and other windings or between metallic inner and outer parts of the inductive component.

The invention has for its object to provide an inductive component of the type mentioned, in which over the prior art significantly improved heat dissipation is achieved.

This object is achieved by an inductive component having the features of patent claim 1.

• der Isolator mantelförmig die wenigstens eine Wicklung mindestens teilweise flächenschlüssig umschließend ausgebildet ist, und
• das Kühlelement als die wenigstens eine Wicklung aufnehmendes Gehäuse mit einem Innenraum ausgebildet ist, wobei die Innenkontur des Innenraums des Gehäuses der Außenkontur des Isolators angepasst ist.

Such an inductive component with at least one winding, wherein the winding is thermally coupled to a cooling element via a thermally conductive insulator, is characterized according to the invention in that

• the insulator jacket-shaped, the at least one winding is formed at least partially enclosing surface-locking, and
• the cooling element is formed as the at least one winding receiving housing having an interior, wherein the inner contour of the interior of the housing is adapted to the outer contour of the insulator.

Since the lateral surface of the winding is at least partially, preferably completely frictionally surrounded by the insulator and this insulator in turn also surface-locking in contact with the housing, a large thermal contact surface between the winding and the housing formed as a cooling element is achieved, thereby realizing a very high cooling performance becomes. At the same time, the installation space of the inductive component is minimized by such an arrangement.

In one embodiment of the invention, the insulator is tubular, in particular designed as a heat pipe, whereby a high heat flux from the winding via this heat pipe in the housing comes to a standstill. The insulator can also be formed from one or more shells or shell elements.

Alternatively, it is provided according to another advantageous embodiment of the invention that the insulator is designed as wound around the at least one winding of a heat conducting foil winding. The advantage of using a heat-conducting foil is that it is well adapted to the surface structure of the winding when the winding is wound to produce the coil, thereby realizing a low heat transfer resistance between the coil and the coil made of the heat-conducting foil. Furthermore, it is possible that the thermally conductive insulator is formed as a pre-bent element.

According to a further embodiment of the invention, the housing is formed on the outside with cooling fins. Thus, the heat dissipation from the winding is substantially improved, since the housing acts with these cooling fins as a heat sink. Such ribs may also or additionally be provided inside the housing.

Furthermore, the housing according to the invention is advantageously formed with at least two, each interface surfaces having housing parts, these housing parts are formed with the interface surfaces such that the insulator between the at least one winding and the connected via the interface surfaces housing parts, in particular screwed, is pressed. By this compression of the insulator between the winding and the housing, a further improvement of the heat dissipation through the housing is achieved. Advantageously, according to the further development, the at least one winding has a cylindrical shape and is circular, oval, stadion-shaped or approximately four- or polygonal in cross-section, which can thus be manufactured in a manner known per se.

According to a further embodiment of the invention, the at least one winding is wound on an insulating tube as a bobbin. This is particularly useful when further development according to the one winding is arranged on a magnetic core. This insulating tube may also be formed of a thermally conductive material.

Such a magnetic core may be formed according to an embodiment of the invention as a ferrite core, dust core, core corrugated or as consisting of several magnetic segments with intermediate insulating elements existing magnetic core. A combination of these materials is also possible.

The mentioned, at least one winding can be known to be formed from a flat wire, a tape roll, round wire or an HF strand.

A further embodiment of the invention provides that the insulator protrudes at one or both ends of the at least one winding, viewed in the axial direction of the winding. As a result, necessary clearance and creepage distances to the housing of the inductive component can be safely met. It is expedient that these distances are filled by suitable potting material.

In another embodiment of the invention, it is provided that between the heat-conducting insulator and the cooling element a further insulation element, in particular an insulating film is arranged. This further improves the dielectric strength of the inductive component.

The thermally conductive insulator is preferably made of a silicone and polyurethane with ceramic and / or quartz filling and preferably has a Shore hardness in the range of about 70 to 80 for this purpose. As thermally conductive insulator can also be used a thermally conductive silicone or polyurethane film.

Figur 1

eine perspektivische Explosionsdarstellung einer Drossel als induktives Bauteil gemäß einer Ausführungsform der Erfindung,

Figur 2

eine Darstellung des induktiven Bauteils gemäß Figur 1 im zusammengebauten Zustand,

Figur 3

ein zweites Ausführungsbeispiel eines induktiven Bauteils in perspektivischer Explosionsdarstellung mit schalenförmig ausgebildeten, wärmeleitenden Isolatoren,

Figur 4

eine Schnittdarstellung des induktiven Bauteils von Figur 3 entlang der dort eingezeichneten Schnittebene,

Figur 5

ein weiteres Ausführungsbeispiel eines induktiven Bauteils in perspektivischer Explosionsdarstellung mit einer zweilagigen Wicklung, und

Figur 6

eine Schnittdarstellung des induktiven Bauteils von Fig. 5 entlang der dort eingezeichneten Schnittebene.

The invention will now be described in detail by means of an embodiment with reference to the accompanying figures. Show it:

FIG. 1

an exploded perspective view of a throttle as an inductive component according to an embodiment of the invention,

FIG. 2

a representation of the inductive component according to FIG. 1 in assembled condition,

FIG. 3

A second embodiment of an inductive component in an exploded perspective view with cup-shaped, heat-conducting insulators,

FIG. 4

a sectional view of the inductive component of FIG. 3 along the cutting plane marked there,

FIG. 5

a further embodiment of an inductive component in a perspective exploded view with a two-ply winding, and

FIG. 6

a sectional view of the inductive component of Fig. 5 along the section plane marked there.

In the following figures, like reference characters designate parts having the same meaning, unless otherwise indicated.

The inductive components 1 according to FIG. 1 represents in an exploded view a throttle with two arranged on a respective magnetic core 6.1 and 6.2 windings 2.1 and 2.2, which in turn are each wound on an insulating tube 5.1 and 5.2 as a bobbin. The FIG. 2 shows this throttle 1 in the assembled state.

On the windings 2.1 and 2.2, a hollow cylindrical insulator 4.1 and 4.2 is arranged in each case, wherein the inner lateral surfaces of these two insulators 4.1 and 4.2 to the outer contour, i. are surface-fit adapted to the lateral surfaces of the two windings 2.1 and 2.2 and preferably rest there.

Thus, these two insulators 4.1 and 4.2 can each be pushed onto the two windings 2.1 and 2.2 as a heat pipe.

Alternatively, a heat-conducting foil is used for the two insulators 4.1 and 4.2, which is wound directly onto the two windings 2.1 and 2.2 to form a coil.

As a cooling element for this throttle 1 is composed of two housing parts 3.1 and 3.2 housing 3, which consists of a lower housing part 3.1 and a housing upper part 3.2. The two housing parts 3.1 and 3.2 each have interface surfaces 3.5 and 3.6, via which the two housing parts 3.1 and 3.2 assembled and bolted together by means of screw connections 7. In this state, the housing 3 has two cylindrical inner spaces, which are formed by an inner space 3.11 or 3.12 of the lower housing part 3.1 together with an inner space 3.21 or 3.22 of the upper housing part 3.2.

The inner contour of these two cylindrical inner spaces corresponds to the cylindrical outer contour of the two insulators 4.1 and 4.2, so that the inner lateral surfaces of the two inner spaces of the housing parts 3.1 and 3.2 lie on the lateral surfaces of the two windings 2.1 and 2.2 surface-locking, so they touch cylindrical.

The screwing of the two housing parts 3.1 and 3.2 via integrally formed on the upper housing part 3.2 flanges 3.7, which rest on the interface surfaces 3.5 of the housing base 3.1, so that the two insulators 4.1 and 4.2 between the two windings 2.1 and 2.2 and the two housing parts 3.1 and 3.2 be pressed. As a result, the heat conduction between the two windings 2.1 and 2.2 and the housing 3 is improved. An improved cooling of the throttle 1 is also achieved in that both the lower housing part 3.1 and the upper housing part 3.2 is equipped with cooling surfaces 3.3 and 3.4 respectively. These cooling surfaces 3.3, 3.4 may have cooling fins. Thus, this housing 3 also assumes the function of a heat sink.

According to FIG. 1 the throttle 1 has two soft magnetic yokes 8.1 and 8.2 connecting the two magnetic cores 6.1 and 6.2. These two yokes 8.1 and 8.2 are each received by an insulation box 9.1 and 9.2, wherein these two insulation boxes 9.1 and 9.2 are each arranged on one end face of the housing 3 and connected to the same. The front side, the throttle 1 is completed by means of an installation cover 10.1 and 10.2 by 11.1 and 11.2 with fixing screws the installation cover 10.1 and 10.2 are screwed together with the insulation boxes 9.1 and 9.2 with the housing 3.

Ferrite cores can be used as magnetic cores 6.1 and 6.2. Alternatively, it is possible to use segmented magnetic cores 6.1 and 6.2, which are each composed of magnet segments 6.11 and 6.21 which are insulated from one another by means of insulating elements 6.12 and 6.22. Instead of or in addition to these insulation segments 6.12, 6.11 and permanent magnet segments can be used. In addition to ferrite cores also powder cores, corrugated cores or a combination of these cores can be used.

In FIG. 3 is shown a further embodiment of an inductive component according to the invention. This embodiment is largely similar to the inductive component of Fig. 1 , However, the in FIG. 1 used, tubular, thermally conductive insulators 4.1, 4.2 now replaced by thermally conductive insulators 4.3, 4.4, 4.5, 4.6, which are cup-shaped, and as the sectional view of FIG. 4 shows, in each case enclose only the upper region and lower region of the windings 2.1, 2.2 and rest there. In the illustrated embodiment, each of the shell-shaped insulators 4.3, 4.4, 4.5 and 4.6 surrounds a winding 2.1, 2.2 by about 90 °. Of course, other angles can also be provided, e.g. B. 60 ° to 120 °.

How particularly good from the sectional view of FIG. 4 it can be seen, however, that the cup-shaped insulators 4.3, 4.4, 4.5 and 4.6 are again inserted between the housing 3.1 or 2 and the winding 2.1 and the winding 2.2 and the housing part 3.1 and 3.2 and preferably placed pressed via the above-mentioned screw. A remaining, free space between the housing components 3.1, 3.2 and the windings 2.1, 2.2 or the aforementioned shell-shaped insulators 4.3, 4.4, 4.5 and 4.6 is expediently with a suitable material, preferably a cast resin, poured out. This material is in the sectional view of FIG. 4 designated by the reference numeral 20. This material is preferably designed as a thermally conductive material.

In FIG. 5 is shown a further embodiment of an inductive component according to the invention. This embodiment differs from the aforementioned embodiments in particular in that here a two-layer winding of the throttle is provided. For this purpose, the already described two windings 2.1, 2.2 are provided within which there is a second layer of windings in the form of windings 2.3 and 2.4. The winding 2.3 is located within the winding 2.1. The winding 2.4 is located inside the winding 2.2. The windings 2.3 and 2.4 are wound on the insulation tubes 5.1 and 5.2. In the present case, but also in the aforementioned exemplary embodiments, these insulating tubes 5.1 and 5.2 can likewise be designed as heat-conducting insulating tubes.

To the two windings 2.1, 2.2, in turn, a tubular, heat-conducting insulator 4.7, 4.8 is arranged. In the exemplary embodiment shown, the two insulators 4.7 and 4.8 are arched, prefabricated insulation elements made of thermally conductive material, with wall sections over the entire length of the insulators 4.7, 4.8 overlapping slightly along the longitudinal extent of these tubular insulators 4.7, 4.8. This overlapping region is marked for the insulator 4.8 by the reference numeral 4.81.

Between the windings 2.1 and 2.3, a similarly constructed, tubular insulator 4.9 is placed. The same applies to the windings 2.2 and 2.4. There is also interposed a tubular insulator 4.10. The overlapping area is identified by the reference numeral 4.101.

In FIG. 6 is the sectional view along the in Fig. 5 shown cutting plane shown. The already known reference numerals are also used there. It is particularly good turn to see that the housing parts 3.1, 3.2 are surface-mounted with their inner walls against the insulators 4.7, 4.8 touching to achieve a good heat dissipation.

Although in FIG. 5 and 6 only two coaxially arranged winding 2.1, 2.2 and 2.3, 2.4 are shown, the principle shown there can readily be applied to even more nested winding, z. For example, three, four, or more.

It should be noted in this context that it is expedient that the insulators 4.1 ... 4.10 also - seen in the axial direction of the windings 2.1, 2.2 and 2.3, 2.4 - over the ends the windings can stand out a bit. This increases the required clearances and creepage distances and thus ultimately the flow resistance of the inductive component.

As a material for the heat-conducting insulators 4.1 ... 4.10, for example, silicone or polyurethane with ceramic filling or quartz filling can be used. In this case, this material should have a Shore hardness in the range of about 70 to 80. It is particularly favorable if this material has a thermal conductivity of approximately greater than or equal to 1.5 W / mK. The thermally conductive insulator may be, for example, a suitably formed thermally conductive silicone or polyurethane film. Such a film must be wound. It is also advisable, in order to avoid the bending process, to provide a correspondingly preformed element as an insulator.

LIST OF REFERENCE NUMBERS

1

Inductive component, choke

2.1

Winding the choke 1

2.2

Winding the choke 1

3

Cooling element, housing

3.1

Housing part, housing lower part of the housing 1

3.11

Interior of the housing base 3.1

3.12

Interior of the housing base 3.1

3.2

Housing part, upper housing part of the housing 1

3.21

Interior of the housing upper part of the housing 1

3.22

Interior of the housing upper part of the housing 1

3.3

Cooling surface of the housing base 3.1

3.4

Cooling surface of the upper housing part 3.2

3.5

Interface surface of the lower housing part 3.1

3.6

Interface surface of the upper housing part 3.2

3.7

Flange of the upper housing part 3.2

4.1

Insulator, heat pipe, winding winding 2.1

4.2

Insulator, heat pipe, winding of the winding 2.2

5.1

Insulation tube of the winding 2.1

5.2

Situation tube of the winding 2.2

6.1

Magnetic core of the winding 2.1

6.11

Magnetic segment of the magnetic core 6.1

6.12

Insulation element of the magnetic core 6.1

6.2

Magnetic core of the winding 2.2.

6.21

Magnetic segment of the magnetic core 6.2

6.22

Insulation element of the magnetic core 6.2

7

screw

8.1

Yoke of the magnetic cores 6.1 and 6.2

8.2

Yoke of the magnetic cores 6.1 and 6.2

9.1

Isolation box of choke 1

9.2

Isolation box of choke 1

10.1

Insulation cover of choke 1

10.2

Insulation cover of choke 1

11.1

fixing screws

11.2

fixing screws

20

Material, casting resin

Claims (17)

Inductive component (1) with at least one winding (2.1, 2.2), wherein the winding (2.1, 2.2) is thermally coupled to a cooling element (3) via a thermally conductive insulator (4.1, 4.2),
characterized in that - The insulator (4.1, 4.2) shell-shaped, the at least one winding (2.1, 2.2) is formed at least partially enclosing surface-locking, and - The cooling element as the at least one winding (2.1, 2.2) accommodating housing (3) with an interior space (3.11, 3.12, 3.21, 3.22) is formed, wherein the inner contour of the interior (3.11, 3.12, 3.21, 3.22) of the housing ( 3) of the outer contour of the insulator (4.1, 4.2) is adjusted. Inductive component (1) according to claim 1,
characterized in that the insulator is tubular, in particular as a heat pipe (4.1, 4.2) is formed. Inductive component (1) according to claim 1,
characterized in that the insulator is formed as around the at least one winding (2.1, 2.2) of a heat conducting foil applied winding (4.1, 4.2). Inductive component (1) according to claim 1,
characterized in that the insulator (4) as a shell (4.3, 4.4, 4.5, 4.6) is formed. Inductive component (1) according to claim 1,
characterized in that the insulator (4.1, 4.2) is formed as a curved, prefabricated element (4.7, 4.8). Inductive component (1) according to one of the preceding claims,
characterized in that the housing (3) on the outside with cooling ribs (3.3, 3.4) is formed. Inductive component (1) according to one of the preceding claims,
characterized in that - The housing (3) with at least two, each interface surfaces (3.5, 3.6) having housing parts (3.1, 3.2) is formed, and - The housing parts (3.1, 3.2) with the interface surfaces (3.5, 3.6) are formed such that the insulator (4.1, 4.2) between the at least one winding (2.1, 2.2) and via the interface surfaces (3.5, 3.6) connected housing parts (3.1, 3.2) pressed, in particular screwed. Inductive component (1) according to one of the preceding claims,
characterized in that the at least one winding (2.1, 2.2) is in particular designed as a flat wire, tape winding, round wire or HF strand preferably cylindrical, oval, stadium-shaped or polygonal. Inductive component (1) according to one of the preceding claims,
characterized in that the at least one winding (2.1, 2.2) is wound on an insulating tube (5.1, 5.2). Inductive component (1) according to claim 1,
characterized in that the insulation tube (5.1, 5.2) is formed of a thermally conductive material. Inductive component (1) according to one of the preceding claims,
characterized in that the at least one winding (2.1, 2.2) is arranged on a magnetic core (6.1, 6.2). Inductive component (1) according to one of the preceding claims,
characterized in that the magnetic core (6.1, 6.2) is a ferrite core, powder core, corrugated core or a combination of these cores. Inductive component (1) according to one of claims 1 to 12, characterized in that the magnetic core (6.1, 6.2) of a plurality of magnetic segments (6.11, 6.21) is constructed with interposed insulating elements (6.12, 6.22). Inductive component (1) according to one of claims 1 to 13, characterized in that the insulator (4.1, 4.2) at one or both ends of the at least one winding (2.1, 2.2) - in the axial direction of the Winding (2.1, 2.2) seen - survives. Inductive component (1) according to one of claims 1 to 14, characterized in that between the thermally conductive insulator (4.1, 4.2) and the cooling element (3), a further insulating element, in particular an insulating film is arranged. Inductive component (1) according to one of claims 1 to 15, characterized in that the heat-conducting insulator (4.1, 4.2) is formed as a thermally conductive silicone film or polyurethane film. Inductive component (1) according to one of claims 1 to 15, characterized in that the heat-conducting insulator (4.1, 4.2) consists of a silicone or polyurethane with ceramic filling with a Shore hardness in the range of about 70 or 80.

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