Electrical device, in particular converter

Abstract

Proposed is an electrical device, in particular a converter, wherein: the electrical device has - a heat sink, - a printed circuit board and - a component fitted on the printed circuit board; the heat sink has a baseplate and mutually parallel cooling fins formed integrally on one side of the baseplate; a fan conveys an air stream which flows along intermediate spaces formed between the cooling fins; the component is arranged on the side of the baseplate which faces away from the cooling fins; the baseplate has a depression into which the component projects; the component is spaced from the heat sink such that an annular gap is formed between the component and the heat sink; the baseplate has mutually spaced apertures extending through it; and the apertures open at one side into one of the intermediate spaces each and at the other side into the annular gap.

Description

[0001] Electrical appliance, especially inverter

[0002] Description:

[0003] The invention relates to an electrical device, in particular an inverter.

[0004] It is generally known that the waste heat from components of an electrical device must be dissipated to the environment.

[0005] The invention is therefore based on the objective of further developing a method for dissipating heat from a component.

[0006] According to the invention, the problem is solved in the electrical device, in particular the converter, according to the features specified in claim 1.

[0007] Key features of the invention in the electrical device, in particular the inverter, are that the electrical device comprises a heat sink, a circuit board, and a component mounted on the circuit board, in particular a heat-generating component, wherein the heat sink has a base plate and cooling fins formed on one side of the base plate and running parallel to each other, wherein a fan conveys an airflow which flows along in spaces formed between the cooling fins, wherein the component is arranged on the side of the base plate facing away from the cooling fins, wherein the base plate has a recess, in particular a dent or a trough, into which the component projects, wherein the component is spaced apart from the heat sink, in particular from the base plate, so that an annular gap is formed between the component and the heat sink, wherein the base plate has continuous, spaced-apart recesses, in particular slots.wherein each of the recesses opens on the one hand into one of the spaces and on the other hand into the annular gap.

[0008] An advantage of this design is that the component is spaced away from the heat sink, thus ensuring sufficient insulation strength. Furthermore, the recess is shaped like a dent. This eliminates the need for additional material, as the wall thickness remains essentially constant, and in particular, varies by less than a factor of three. Therefore, the base plate is shaped in the recess area to follow the outer contour of the component, maintaining the aforementioned distance. Airflow passes through the recesses into the annular gap, thus dissipating heat from the component. Since the component is cylindrical and the base plate follows the shape of the recess, the resulting space between the component and the base plate is an annular gap. Outside the recess area, the base plate is preferably cuboid in shape.

[0009] In an advantageous embodiment, the heat sink, comprising the base plate and the cooling fins, is formed in one piece, particularly as a single unit. The advantage here is that the heat sink can be easily manufactured as a casting. Furthermore, no additional heat transfer needs to be considered for heat conduction.

[0010] In an advantageous design, the shape of the recess follows the outer shape of the component. It is advantageous that the surface of the base plate facing the component essentially follows the contour of the component. The wall thickness of the base plate can remain essentially constant. Thus, efficient heat dissipation can be achieved without additional material.

[0011] In an advantageous embodiment, the heat sink is spaced away from the circuit board. This is advantageous because electrical insulation can be ensured. In an advantageous embodiment, the distance between the base plate and the heat sink is always greater than a minimum distance. This is advantageous because a specified minimum voltage clearance can be maintained.

[0012] In an advantageous embodiment, the distance between the circuit board and the heat sink is always greater than a certain minimum distance. An advantage of this is that electrical insulation can be ensured.

[0013] In an advantageous embodiment, the cooling fins extend at their end region facing away from the base plate to a plane that is aligned parallel to the base plate. The advantage here is that this plane is spaced away from the circuit board, thus ensuring a well-defined and reliable insulation distance.

[0014] In a preferred embodiment, the circuit board is aligned parallel to the base plate. An advantage of this is that an insulation distance can be easily ensured.

[0015] In a preferred design, the heat sink is a cast part. The advantage here is that simple and cost-effective manufacturing is achievable.

[0016] In an advantageous embodiment, the heat sink has a base area which is connected to the base plate, and the heat sink, including the base area, base plate, and cooling fins, is manufactured as a single piece, particularly in one component. An advantage of this is that the heat sink not only dissipates heat from the component itself, but also from other components that are thermally connected to the base area.

[0017] In an advantageous embodiment, the heat sink is connected to a housing part to which the printed circuit board (PCB) is connected. It is advantageous that the housing part can be manufactured from injection-molded plastic and keeps the PCB spaced apart from the heat sink, particularly while maintaining an insulation distance. In an advantageous embodiment, the smallest clear diameter of the cross-section of each recess is greater than twice the square root of the smallest clear cross-sectional area of ​​the annular gap, particularly where the normal direction of the cross-sectional area is tangentially aligned to the annular axis of the annular gap. It is advantageous that no disruptive flow resistance is present.

[0018] In an advantageous embodiment, the recess nearest the fan is shaped such that the airflow conveyed by the fan is deflected and flows tangentially into the annular gap with respect to the annular axis of the gap. It is advantageous that the recess not only functions as a passage but also as a deflector of the airflow to prevent turbulence.

[0019] In an advantageous embodiment, the recess closest to the fan, relative to the annular axis of the annular gap, does not extend purely radially through the base plate, and / or the recess closest to the fan, with a decreasing radial distance relative to the annular axis, increasingly deflects the airflow in the circumferential direction. It is advantageous that this deflection of the airflow can be achieved while it is passing through the base plate.

[0020] Further advantages arise from the dependent claims. The invention is not limited to the combination of features in the claims. For those skilled in the art, further meaningful combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent, particularly from the problem statement and / or the problem arising from a comparison with the prior art. The invention will now be explained in more detail with reference to schematic illustrations.

[0021] Figure 1 shows an oblique view of the interior of an electrical device according to the invention, in particular an inverter, which has a heat sink.

[0022] Figure 2 shows a longitudinal section of the interior of the electrical device with the housing 1 removed.

[0023] Figure 3 shows a cross-sectional view of the electrical device.

[0024] Figure 4 shows the heat sink in an oblique view.

[0025] As shown in the figures, the electrical device has a heat sink on whose base plate 10 cooling fins 2 are formed parallel to each other and / or extending.

[0026] A fan 6 generates an airflow that flows through the spaces 30 between the cooling fins 2. A housing 1 mounted on the heat sink, together with the heat sink, defines the spaces 30.

[0027] A component 5 of the electrical device generates waste heat during operation, which must be dissipated via the cooling fins 2.

[0028] For this purpose, component 5 projects into a recess formed as a pocket or basin on the base plate 10 of the heat sink, while component 5 is spaced apart from the heat sink. The recess preferably follows the shape of component 5, so that the distance between the heat sink and component 5 remains constant over a wide area.

[0029] The base of the recess, designed as a partition wall connecting the cooling fins 2, extends perpendicular to the direction of extension of the cooling fins 2 and has continuous recesses, each of which opens into one of the spaces 30 between the cooling fins 2. The partition wall thus connects the cooling fins 2.

[0030] The base plate 10 connects the cooling fins 2 and is spaced away from component 5.

[0031] Component 5 is mounted on a printed circuit board 3. Preferably, component 5 is a choke coil.

[0032] Component 5 is located on the side of the base plate 10 facing away from the cooling fins 2.

[0033] In the area of ​​the depression, the base plate 10 is shaped to correspond to a dent or hollow. Thus, the wall thickness of the base plate 10 in the area of ​​the depression is essentially constant or only varies slightly.

[0034] Towards circuit board 3, the cooling fins terminate in a plane that is aligned parallel to circuit board 3. Thus, the distance of all cooling fins 2 to circuit board 3 is constant.

[0035] Since the base plate 10 is also aligned parallel to the circuit board 3, the cooling fins 2 extend less in the normal direction to the plane in the area of ​​the dent or depression than outside this area. Therefore, the cooling fins 2 are shorter in the normal direction in the area of ​​the dent or depression than outside this area.

[0036] The heat sink together with base plate 10 and cooling fins 2 is preferably made in one piece, in particular as an aluminum casting.

[0037] The choke acts as a damping element to reduce current fluctuations, especially as part of a mains choke.

[0038] If the cross-sectional area of ​​the recesses is larger than the cross-sectional area of ​​the annular gap formed between component 5 and the heat sink, the airflow delivered by the fan flows through the annular gap 4, thus improving the heat dissipation from component 5. To reduce turbulence, the recess closest to the fan is shaped such that the airflow delivered by the fan is deflected and enters the annular gap 4 tangentially with respect to the annular axis of the annular gap. For this purpose, the recess does not extend purely radially through the base plate 10 with respect to the annular axis of the annular gap, but is deflected increasingly circumferentially with decreasing radial distance with respect to the annular axis. In this way, the air flows into the annular gap 4 as tangentially as possible, and flow turbulence is suppressed.

[0039] In further embodiments according to the invention, the heat sink has a base area which is connected to the base plate 10 and is made in one piece, in particular in one part.

[0040] In further embodiments according to the invention, component 5 is not a choke, but a capacitor.

[0041] Reference symbol list

[0042] 1 Housing 2 Cooling fin

[0043] 3 circuit boards

[0044] 4 annular gap

[0045] 5 components

[0046] 6 fans 7 partition

[0047] 8 Exclusion

[0048] 9 Electronic components, especially those mounted on the circuit board 3

[0049] 10 Base plate

[0050] 30 spaces between the cooling fins 2

Claims

Patent claims:

1. Electrical device, in particular an inverter, wherein the electrical device comprises a heat sink, a printed circuit board and a component mounted on the printed circuit board, in particular a heat-generating component, wherein the heat sink has a base plate (10) and cooling fins formed on one side of the base plate (10) and parallel cooling fins, wherein a fan conveys an airflow which flows along in spaces (30) formed between the cooling fins, characterized in that the component is arranged on the side of the base plate (10) facing away from the cooling fins, wherein the base plate (10) has a recess, in particular a dent or a trough, into which the component projects, wherein the component is spaced apart from the heat sink, in particular from the base plate (10), such that an annular gap (4) is formed between the component and the heat sink, wherein the base plate (10), in particular the intermediate wall (7), has continuoushas spaced-apart recesses, in particular slots, wherein each of the recesses opens on one side into one of the spaces (30) and on the other side into the annular gap (4).

2. Electrical appliance according to claim 1, characterized in particular in that the bottom of the recess is designed as an intermediate wall (7) which is a part of the base plate (10) and which connects the cooling fins.

3. Electrical appliance according to claim 1, characterized in that the heat sink, comprising the base plate (10) and the cooling fins, is formed in one piece, in particular in one piece.

4. Electrical device according to one of the preceding claims, characterized in that the shape of the recess follows the outer shape of the component.

5. Electrical device according to one of the preceding claims, characterized in that the heat sink is spaced away from the circuit board.

6. Electrical device according to one of the preceding claims, characterized in that the distance between the base plate (10) and the heat sink is always greater than a minimum distance.

7. Electrical device according to one of the preceding claims, characterized in that the distance between the circuit board and the heat sink is always greater than a minimum distance.

8. Electrical appliance according to one of the preceding claims, characterized in that the cooling fins extend at their end region facing away from the base plate (10) to a plane which is aligned parallel to the base plate (10).

9. Electrical device according to one of the preceding claims, characterized in that the circuit board is aligned parallel to the base plate (10).

10. Electrical appliance according to one of the preceding claims, characterized in that the heat sink is a cast part.

11. Electrical appliance according to one of the preceding claims, characterized in that the heat sink has a base area which is connected to the base plate (10) and the heat sink together with the base area, a base plate (10) and cooling fins is made in one piece, in particular in one piece.

12. Electrical device according to one of the preceding claims, characterized in that the heat sink is connected to a housing part to which the circuit board is connected.

13. Electrical device according to one of the preceding claims, characterized in that the smallest clear diameter of the cross-section of each recess is greater than twice the square root of the smallest clear cross-sectional area of ​​the annular gap, in particular wherein the normal direction of the cross-sectional area is tangentially aligned to the annular axis of the annular gap.

14. Electrical device according to one of the preceding claims, characterized in that the recess nearest to the fan is shaped in such a way that the airflow conveyed by the fan is deflected and flows tangentially into the annular gap (4) with respect to the annular axis of the annular gap.

15. Electrical device according to one of the preceding claims, characterized in that the recess nearest to the fan does not extend purely radially through the base plate (10) with respect to the annular axis of the annular gap and / or that the recess nearest to the fan increasingly deflects the airflow in the circumferential direction with a radial distance decreasing with respect to the annular axis.

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