INDUCTIVE COMPONENT

Abstract

An inductor includes a winding that has a predefined inductance, a soft magnetic winding core, and a housing that has a cooling surface for discharging heat from the inductor. This housing encases the winding.

Claims

1. An inductor, comprising: a winding with a predefined inductance; a soft magnetic winding core; and a housing with a cooling surface configured to discharge heat from the inductor, wherein the housing is applied to the winding with an injection molding process.

2. The inductor according to claim 1, wherein the housing comprises a thermally conductive thermosetting polymer.

3. The inductor according to claim 1, wherein the winding core is ring-shaped.

4. The inductor according to claim 1, wherein the winding core is inside the housing.

5. The inductor according to claim 1, wherein the winding core is outside the housing.

6. The inductor according to claim 5, wherein the winding core acts on numerous windings in individual housings.

7. The inductor according to claim 1, wherein the winding core is made of two parts that are placed on the windings.

8. The inductor according to claim 1, wherein the inductor comprises a choke.

9. The inductor according to claim 1, wherein the inductor is configured for use in an electric drive train.

10. A method for producing an inductor, the method comprising: providing a soft magnetic winding core; placing a winding on the winding core; and coating the winding core and winding to form a housing.

11. A method for producing an inductor, the method comprising: providing a winding; coating the winding to form a housing; and placing a soft magnetic winding core on the housing.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0023] FIGS. 1, 2, and 3 show a first variation of an inductor;

[0024] FIG. 4 shows a second variation of an inductor;

[0025] FIG. 5 shows a flow chart for a method;

[0026] FIGS. 6 and 7 show sectional views of a second variation of an inductor;

[0027] FIGS. 8, 9, and 10 show the second variation of an inductor with winding encased in a housing from various perspectives; and

[0028] FIGS. 11, 12, and 13 show numerous windings with individual housings in an external winding core from various perspectives.

DETAILED DESCRIPTION

[0029] FIG. 1 shows a first variation of an inductor 100. This inductor 100 forms a choke that is preferably designed for use as a passive power component in a switching circuit. The switching circuit can comprise a power converter or control unit for a motor. In one embodiment, the switching circuit is part of a drive train. The switching circuit can be used in a motor vehicle, e.g. a motorcycle, passenger automobile, truck, or bus.

[0030] The component 100 comprises an electrical conductor 105 that forms a winding 110. This conductor 105 can be wound onto a non-magnetic support element 115. The windings of the conductor 105 can form a single layer, as shown in the drawing, or they can form numerous layers. In this embodiment, the electrical conductor 105 is formed by a flat band. It can also have a round cross section. The ends of the conductor 105 can form terminals 120 on the winding 110.

[0031] The windings of the conductor 105 preferably encircle a winding core 125 composed of a single part or multiple parts. The winding core 125 can be made of ferrite or a powdered material. The winding core 125 can also be on the outside of the winding 110.

[0032] The winding 110 and the winding core 125 are encased in a housing that is preferably formed on the winding 110 and the winding core 125 in an injection molding process. The housing 130 encases the winding 110 and winding core 125, as well as the optional support element 115, but leaves the terminals 120 exposed. A fastener 135 can be formed on the housing 130 in order to be able to mechanically secure the inductor 100.

[0033] A cooling surface 140 is also formed on the housing 130, at which heat from the inductor is discharged to an element bearing thereon. The housing 130 is preferably made of a thermally conductive material for this. This element can comprise a heat sink for a cooling channel for a coolant. The cooling surface 140 can be thermally bonded to the cooling element by a thermally conductive element 145. The thermally conductive element 145 can comprise a thermally conductive pad, thermally conductive paste, or thermally conductive adhesive. The heat generated in the winding 110 is then discharged through the thermally conductive housing 130 and the thermally conductive element 145.

[0034] FIG. 2 shows numerous integrated inductors 100 of the type shown in FIG. 1. There are three windings 110 on a single, multi-part winding core 125 shown therein. To encase the assembly in FIG. 2 in a housing 130, it can be placed in a mold and coated with the housing 130. This coating is preferably a plastic, in particular a thermoset, that can no longer be reshaped after it has cured. The plastic can preferably be a thermally conductive plastic.

[0035] FIG. 3 shows the assembly in FIG. 2 encased in the housing 130. The terminals 120 on the windings 110 extend out of the top of the housing 130, and there are fasteners 135 on the side.

[0036] FIG. 4 shows a second variation of an inductor 100. This also has numerous windings 110 and a single, multi-part winding core 125. In this variation, the housing 130 encases each winding 110 separately, and the winding core 125 is outside the housing 130.

[0037] Like the embodiments shown in FIGS. 1 to 3, the windings 110 are cylindrical, wherein the elements forming the winding core 125 can be placed thereon from opposing axial directions in relation to the axes of the cylinders. The winding core 125 is preferably shaped such that it substantially fills the inside of a winding 110 and encases the outside thereof. The terminals 120 for the windings 110 can extend out of the housing 130. The elements of the winding core 125 can be glued to one another or the housing 130 with an adhesive.

[0038] This embodiment has a bracket 150 that holds the inductor 100 together and/or can be attached to an external object. The bracket 150 in this embodiment has holes through which the terminals 120 on the windings 110 can pass. A cooling surface 140 on the housings 130 encasing each winding 110 is preferably on the surface opposite the terminals 120.

[0039] One or more fasteners 135 can be formed on the bracket 150, which can be used to press a cooling surface 140 on the housing 130 against another element. It can be seen herein that a section of the housing 130 that has the cooling surface 140 extends out of the winding core 125, and that the cooling surface 140 is not flat, but instead follows the rounded form of the housing 130.

[0040] FIG. 5 shows a flow chart for a method 500 for producing an inductor 100. The method 500 has first and second variations, with which either the first or second variation of an inductor 100 described herein can be produced.

[0041] In the first variation, the method 500 begins with step 505, in which a winding core 125 is provided. The winding core 125 can be composed of a single piece or two pieces. In step 510, a winding 110 is placed on the winding core 125. The winding 110 is preferably wound separately in advance, and then placed on the respective winding core 125. The winding core 125, preferably comprising two parts, is then glued together. In this case, this means that the parts thereof are glued together. A plate 155, made of ferrite in particular, can then be glued to numerous winding cores 125.

[0042] In step 515, the winding core 125 or the winding 110, as well as the support structure 115, can then be coated to form the housing 130. The assembly composed of the winding core 125 and the winding can then be placed in a mold and secured in place. Spacings between the assembly and the mold can be predefined in all directions for this. A liquid or paste-like compound can then be injected into the spaces, such that the compound encases the assembly. After hardening or curing, the compound forms the housing 130.

[0043] The housing 130 has a cooling surface 140 that can bear on a cooling element. In step 520, a thermally conductive element 145 can be attached to the cooling surface 140. The housing 130 can then be attached to a cooling element in step 525.

[0044] In the second variation, the method 500 starts with step 530, in which a winding 110 is provided, which can be self-supporting or on a support element 115. In step 535, the winding 110 can be encased in a housing 130. The winding 110 can be placed in a mold for this, and encased in a liquid or paste-like compound. Once the compound has cured sufficiently, the mold can be opened and the winding 110 encased in the housing 130 can be removed. An external winding core 125 can then be placed on the housing 130 in step 540. This winding core 125 can also be a single piece, or it can be composed of multiple parts. The method can then continue with the steps 520 and 525 described in the first variation.

[0045] FIGS. 6 and 7 show sectional views of a second variation of an inductor 100. FIG. 6 shows the winding 110 cut along the longitudinal axis thereof, and FIG. 7 show a lateral cut. The winding core 125 is made of four parts in this embodiment (see FIG. 4). A thermally conductive element 145 that bears on a cooling element 605 is attached to the cooling surface 140. The inductor 100 can be mechanically attached to a cooling element 605 with the fasteners 135 on the bracket 150.

[0046] FIGS. 8, 9, and 10 show the second variation of a winding 110 encased in a housing 130 described herein from various perspectives. The outer winding core 125 of the inductor 100 has not yet been placed thereon.

[0047] FIGS. 11, 12, and 13 show the second variation of an inductor 100 described herein, with numerous windings 110 in individual housings 130 and an external winding core 125, from various perspectives.

[0048] The winding core 125 in FIG. 11 has multiple parts. Each winding 110 has two dedicated elements. Two other elements of the winding core 125 extend over all three of the windings 110 shown herein. For purposes of clarity with regard to explaining the structure, one of the dedicated elements, and one of the shared elements of the winding core 125 have been omitted.

[0049] The assembly shown in FIG. 11 is shown with all of the elements of the winding core 125 and the bracket 150 in FIG. 12.

[0050] FIG. 13 shows the inductive element shown in FIG. 12 from another perspective.

REFERENCE SYMBOLS

[0051] 100 inductor [0052] 105 conductor [0053] 110 winding [0054] 115 support element [0055] 120 terminal [0056] 125 winding core [0057] 130 housing [0058] 135 fastener [0059] 140 cooling surface [0060] 145 thermally conductive element [0061] 150 bracket [0062] 155 plate [0063] 500 method [0064] 505 providing the winding core [0065] 510 placing the winding on the winding core [0066] 515 encasing the winding core and winding [0067] 520 providing the housing with a thermally conductive element [0068] 525 mounting the housing on the cooling element [0069] 530 providing the winding [0070] 535 coating the winding [0071] 540 placing the winding core thereon [0072] 605 cooling element