Electrical device
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-04-23
- Publication Date
- 2026-03-25
AI Technical Summary
Existing electrical devices face challenges in simple production and maintenance, particularly in ensuring proper alignment and secure electrical connections for heat-generating components like power semiconductors, which can lead to inefficiencies in heat dissipation and potential tilting issues during assembly.
The electrical device incorporates a sheet metal housing with a cover that includes a guide groove and guide rib for centering, along with a plastic centering dome and pins for precise alignment, and a press-fit socket with a screw that secures the circuit board to a heat sink for improved heat transfer and grounding, while allowing for easy disassembly without high-voltage testing.
This design prevents tilting during assembly, enhances heat transfer through secure mechanical and electrical connections, and simplifies production and maintenance by integrating centering features and allowing for cost-effective production with plastic components.
Smart Images
Figure EP2024061076_21112024_PF_FP_ABST
Abstract
Description
[0001] electrical appliance
[0002] Description:
[0003] The invention relates to an electrical device.
[0004] It is generally known that an electrical device has a heat-generating component, such as a power semiconductor, which is connected to a heat sink for heat dissipation.
[0005] The invention is therefore based on the object of developing an electrical device which is to enable simple manufacture and / or maintenance.
[0006] From DE 102014 004 798 A1, an electrical device is known as the closest prior art.
[0007] According to the invention, the object is achieved in the electrical device according to the features specified in claim 1.
[0008] Important features of the invention in the electrical device are that the electrical device, in particular a converter or inverter, has power electronics, in particular a power section, and signal electronics, in particular a control section, wherein the power electronics has a sheet metal housing which, together with a cover, forms a housing, wherein the signal electronics has a signal electronics housing which is placed on the power electronics, wherein the cover has a connecting tab through which a mating connector part of the power electronics protrudes, wherein a connector part of the signal electronics is connected to the mating connector part, wherein a guide groove is formed in the cover, in particular wherein the guide groove extends parallel to the plug connection direction, wherein a guide rib formed on an inner side of the signal electronics housing protrudes into the guide groove and / or is guided by it,wherein at least one first centering dome is arranged on the sheet metal housing and projects towards the signal electronics housing, wherein a screw projects through the centering dome, which also projects through the signal electronics housing and is screwed into a threaded bore of the power electronics, wherein a hollow centering dome, in particular made of plastic, is formed on the connecting tab and projects towards the signal electronics housing, in particular parallel to the plug connection direction of the plug connection formed from the plug connector part and the mating plug connector part, wherein a pin, in particular a cross pin, is formed on the signal electronics housing and projects into the hollow centering mandrel, in particular for centering the signal electronics housing relative to the sheet metal housing.
[0009] The advantage here is that tilting is prevented when placing the signal electronics onto the power electronics, as the pin, the guide groove, and the connector itself represent three centering elements with different modes of action. Tilting is prevented by over-determining the three elements, each with different modes of action and thus with tolerances in different directions. The cover is a crucially important centering element, as it provides the majority of the centering elements.
[0010] In an advantageous embodiment, the connecting tab on the cover is angled. This is advantageous because different spatial directions are taken into account when aligning the signal electronics housing.
[0011] In an advantageous embodiment, the cover is a plastic injection-molded part. This has the advantage that it enables simple, cost-effective production, and the centering means can be integrated simply by shaping without additional effort. In an advantageous embodiment, projecting pins formed on the cover project into depressions or recesses in a base plate of the electrical device, wherein the sheet metal housing is connected to the base plate, wherein a sheet metal edge of the sheet metal housing projects into a groove in the cover, in particular wherein the sheet metal edge is pivoted into the groove by a pivoting movement around the connecting line of the pins, in particular during assembly of the electrical device, and thus projects into it. It is advantageous that the smallest clear diameter of the depressions is larger than the largest outer diameter of the pins.This allows the cover to pivot when the pins are inserted into the recesses. During this pivoting movement, which occurs after the pins are inserted into the recesses, the sheet metal edge is inserted, or rather pivoted, into the groove.
[0012] In an advantageous embodiment, the cover has a knockout area, particularly after knocking out the area, a screw becomes accessible that secures an electrical ground connection or PE connection. This is advantageous because this connection can be disconnected or made without making any other changes, and therefore no testing, such as high-voltage testing or the like, is necessary.
[0013] In an advantageous embodiment, the electrical device, in particular the power electronics, has a printed circuit board which is equipped with a heat-generating component, in particular a power semiconductor, a heat sink with at least one cooling fin and a housing part of the sheet metal housing, wherein a socket, in particular a press-in socket, is inserted into a recess of the cooling fin, wherein a screw, the screw head of which presses the printed circuit board with the component towards the heat sink, is screwed into an internal thread of the socket, wherein the socket has a polygonal area which is pressed into the housing part.
[0014] The advantage here is that, on the one hand, the socket is firmly connected to the housing part, and, on the other hand, the screw, when screwed into the socket, positions and / or presses the socket against a step of the heat sink. This presses the circuit board with the component against the heat sink, improving and ensuring heat transfer. At the same time, the screw and press-in nut serve as an electrical ground connection for the housing part, connecting it to a conductor track on the circuit board.
[0015] To increase the safety of the electrical earth connection, the connection can optionally be made double and thus more secure.
[0016] In an advantageous embodiment, the socket has a toothing cut into the material of the cooling fin. This ensures that the heat sink is electrically securely connected and grounded to the socket, and thus also to the screw and the housing part. A PE connection can also be implemented instead of the ground connection.
[0017] In an advantageous embodiment, the toothing is an external toothing. The advantage here is that the toothing cuts into the recess of the heat sink.
[0018] In an advantageous embodiment, the screw extends through the heat sink, in particular through the cooling fin. This advantageously provides an electrical connection between the circuit board and the housing part.
[0019] In an advantageous embodiment, the housing part is arranged on the side of the heat sink facing away from the circuit board, and / or the circuit board is arranged on the side of the heat sink facing away from the housing part. Advantageously, the housing part can be electrically connected by means of the screw to a conductor track of the circuit board, which can be arranged on the other side of the heat sink in a mechanically protected manner.
[0020] In an advantageous embodiment, the housing part is manufactured as a stamped and bent part from sheet metal. This is advantageous because it allows for simple manufacturing.
[0021] In an advantageous embodiment, the polygonal region is arranged flush with the housing part on at least one side of the housing part, in particular on the side of the housing part facing away from the heat sink.
[0022] In an advantageous design, the polygonal area on the bushing protrudes radially. This has the advantage of achieving a high degree of rotational stability.
[0023] In an advantageous embodiment, the polygonal area is spaced apart from the toothing. It is advantageous that the housing part is spaced apart from a step in the receiving area of the circuit board against which the socket is positioned.
[0024] In an advantageous embodiment, the recess is an interruption in the cooling fin. It is advantageous that the cooling fin has a thickened area in which a hole is provided as a recess.
[0025] In an advantageous embodiment, the bushing is made of steel. This allows for simple and cost-effective production.
[0026] In a preferred embodiment, the heat sink is made of aluminum. This allows the bushing to easily cut into the heat sink material.
[0027] In an advantageous embodiment, the cooling fin has a thickened portion that is interrupted by the recess, in particular, the bushing is inserted into the recess and thus accommodated in the thickened portion. This is advantageous because the bushing can be accommodated easily and securely.In an advantageous embodiment, a further socket, in particular a further press-in socket, is inserted into a further recess of a further cooling fin of the heat sink, wherein a further screw, the screw head of which presses the circuit board with a further component towards the heat sink, is screwed into an internal thread of the further socket, wherein the further socket has a further polygonal area which is also pressed into the housing part, wherein the further socket has a further toothing which is cut into the material of the further cooling fin, wherein the further toothing is also an external toothing, wherein the further screw projects through the heat sink, in particular through the further cooling fin. The advantage here is that a sufficiently secure earth connection can be established. This is because the two screws function as an independently functioning electrical earth wire or PE wire.If one of the screws fails, the other one ensures the function.
[0028] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art. The invention will now be explained in more detail with reference to schematic illustrations:
[0029] Figure 1 shows a cross section through a region of an electrical device according to the invention, wherein a socket 1 is used.
[0030] Figure 2 shows an oblique view of a cut-away area of the electrical device.
[0031] Figure 3 shows an oblique view of the socket 1.
[0032] Figure 4 shows the connection of the sockets 1 with a housing part 5 of the electrical device.
[0033] Figure 5 shows the signal electronics housing 50 of the electrical device in an oblique view.
[0034] Figure 6 shows a cover 60 of the electrical device in an oblique view.
[0035] In Figure 7, the cover 60 is shown from a different viewing direction.
[0036] In Figure 8, the electrical device is shown in an oblique view without the signal electronic housing 50.
[0037] Figure 9 shows the electrical device in an oblique view.
[0038] As shown in the figures, the electrical device has a circuit board 3 which is pressed towards a heat sink 2 by the screw head of a screw 4.
[0039] Thus, a heat-generating component, in particular a power semiconductor, mounted on the circuit board 3 is pressed against the heat sink 2, in particular to improve the thermal coupling of the component to the heat sink 2.
[0040] The bushing 1 is preferably designed as a press-in bushing. The bushing 1 is inserted into a recess, in particular an interruption, of a cooling fin 20 of the heat sink 2 and has an internal thread into which a threaded portion of the screw 4 is screwed. The bushing 1 is supported in the cooling fin 20 at a step of the cooling fin 20.
[0041] The bushing 1 has a polygonal portion 31, in particular a hexagonal portion, on which the cooling fin 20 protrudes and is pressed into a housing part 5 made of sheet metal. Thus, the bushing 1 is non-rotatably embedded in the housing part 5 and non-rotatably connected to the housing part 5.
[0042] At the end region of the bushing 1 facing away from the polygonal region 31, the bushing 1 has a toothing 30 with which the bushing 1 is inserted into the cooling fin 20 in such a way that the toothing 30 is cut into the material of the cooling fin 20.
[0043] The heat sink 2 including the cooling fin 20 is preferably made of aluminum; the bushing 1 is preferably made of steel.
[0044] The sheet metal of the housing part 5 is preferably made of sheet steel. In particular, the housing part 5 is designed as a stamped and bent part.
[0045] The toothing 30 is designed as an external toothing.
[0046] The housing part 5 is preferably arranged on the side of the heat sink 2 facing away from the circuit board 3.
[0047] The housing part 5 is detachably connected to the heat sink.
[0048] A pressure plate 7 is arranged between the screw head and the circuit board 3 so that the force flow introduced by the screw 4 is spread out and thus the circuit board 3 is protected from excessive pressure. The pressure plate 7 is preferably made of metal, so that the housing part 5 is electrically connected to a conductor track of the circuit board 3 via the metallic bushing 1 and the metallic screw 4 as well as the metallic pressure plate 7. In this way, an earth connection and / or PE connection can be provided for the housing part 5. The screw axis of the screw 4 is aligned perpendicular to the direction of extension of the cooling fin 20.
[0049] In further embodiments according to the invention, the component is a power module which comprises a plurality of power semiconductors.
[0050] As shown in more detail in Figures 5 to 9, the electrical device, preferably designed as an inverter or converter, has a sheet metal housing 80 that encloses the power electronics of the electrical device and is designed for installation in a control cabinet. On one side of the electrical device, the sheet metal housing 80 is supplemented by a cover 60, in particular a plastic cover, which is connected to the sheet metal housing 80, and on a bottom side by a base plate 67.
[0051] A signal electronics unit, in particular the signal electronics housing 50, is placed on the power electronics unit, in particular on the sheet metal housing 80 including the cover 60, and is connected by means of screws.
[0052] The cover 60 is manufactured as a plastic injection-molded part and has protruding pins 61, which are inserted into recesses in the base plate 67. By pivoting around the connecting line of the pins 61, the sheet metal edges of the sheet metal housing 80 are pivoted into grooves 66 of the cover 60 during assembly of the electrical device.
[0053] Thus, at least one sheet metal edge protrudes into one of the grooves 66 of the cover 60. Likewise, another sheet metal edge of the cover 60 protrudes into another groove 66 of the cover 60. Thus, the cover 60 can be precisely aligned and centered relative to the sheet metal housing 80.
[0054] The cover 60 has, at its end region facing away from the pins 61, a connecting tab 62 which is bent at a bending angle of 90° from the rest of the cover 60. This connecting tab 62 has a centering hole 63 passing through the connecting tab 62 and a protruding centering dome 64 which is hollow.
[0055] Thus, a first of the screws can be passed through the centering dome 64. The cover 60 has a locking lug so that the cover 60 can be clipped onto the sheet metal housing 80.
[0056] The sheet metal housing has at least two hollow centering domes 82, which are realized as press-in bushings or screw bushings and are connected to the sheet metal housing 80 accordingly.
[0057] One of the centering domes 82 protrudes through the centering hole 63 and thus supports the centering of the cover to the sheet metal housing 80.
[0058] A second screw projects through the centering dome 82 which projects through the centering hole 63.
[0059] A mating connector part 81 projects through a further recess in the connecting tab 62.
[0060] The cover 60 has a guide groove 70 on one of its sides, which is aligned parallel to the plug-in direction of the signal electronics.
[0061] When placing the signal electronics onto the power electronics, the signal electronics housing 50 is guided in such a way that tilting during placement is prevented.
[0062] For this purpose, the signal electronics housing 50 has at least one guide rib 51 on its inner side, which is received and guided in the guide groove 70, in particular when placing the signal electronics housing 50 on the sheet metal housing 80.
[0063] A printed circuit board 52, which is equipped with signal electronics components, is housed in the signal electronics housing 50. Furthermore, the printed circuit board 52 is equipped with a connector part 53, which is connected to the mating connector part 81 of the power electronics, which protrudes through the connecting tab 62.
[0064] Tilting is further prevented by a cross pin 54, which is formed on the signal electronics housing 50, projecting into the centering dome 64. Thus, the spatial alignment of the connector housing 50 relative to the power section of the electrical device is achieved by the guide rib 51 or several such ribs, which project into corresponding guide grooves of the power section, together with the cross pin 54 inserted into the centering dome 64 and the connector part 53, which is or is plugged into the mating connector part 81.
[0065] In addition, the centering domes 82 protrude into corresponding cavities of the signal electronics, so that, in particular coming from the outside, screws can be screwed through the signal electronics and through the cavities of the signal electronics as well as through the centering domes 82 into corresponding internal threads of the power electronics.
[0066] The cover 60 thus provides pre-centering when attaching the signal electronics and also performs the housing function of the power electronics. Furthermore, an RFID tag located in the power electronics can be read without hindrance because the cover 60 is made of plastic.
[0067] The cover 60 is easy to label. Additionally, warning labels can be incorporated into the shape of the cover 60, as well as nameplate nests, i.e., recesses suitable for attaching nameplates.
[0068] The cover 60 is made of electrically insulating material.
[0069] The cover 60 also has a knockout area 60, so that after removing the knockout area 60 with a tool, in particular a screwdriver, a screw of the power electronics can be actuated, in particular rotated, wherein an electrical earth connection or electrical PE connection can be secured by means of the screw.
[0070] List of reference symbols
[0071] 1 bushing, especially press-in bushing
[0072] 2 heat sinks
[0073] 3 circuit board
[0074] 4 screw
[0075] 5 Housing part
[0076] 6 Heat-generating component
[0077] 7 printing plate
[0078] 20 cooling fins
[0079] 30 Gearing
[0080] 31 Polygonal area, especially hexagonal area
[0081] 50 signal electronics housings
[0082] 51 Guide rib
[0083] 52 printed circuit board with signal electronic components
[0084] 53 Connector part
[0085] 54 Cross pin
[0086] 60 Cover, especially plastic cover
[0087] 61 cones
[0088] 62 connecting strap
[0089] 63 Centering hole
[0090] 64 Centering dome
[0091] 65 knockout area
[0092] 66 grooves
[0093] 67 Base plate
[0094] 70 guide groove
[0095] 80 sheet metal housings for power electronics
[0096] 81 Mating connector part
[0097] 82 Centering dome
[0098] 90 recess, through the signal electronics housing 50
Claims
Patent claims:
1. An electrical device, in particular a converter or inverter, wherein the electrical device comprises power electronics, in particular a power section, and signal electronics, in particular a control section, wherein the power electronics comprises a sheet metal housing forming a housing with a cover (60), wherein the signal electronics comprises a signal electronics housing (50) which is placed on the power electronics, wherein the cover (60) has a connecting tab (62) through which a mating connector part (81) of the power electronics protrudes, wherein a connector part (53) of the signal electronics is connected to the mating connector part (81), wherein a guide groove (70) is formed in the cover (60), in particular wherein the guide groove (70) extends parallel to the plug connection direction, wherein a guide rib (51) formed on an inner side of the signal electronics housing protrudes into the guide groove (70) and / or is guided by it,wherein at least one first centering dome (82) is arranged on the sheet metal housing and projects towards the signal electronics housing (50), wherein a screw (4) projects through the centering dome (82), which also projects through the signal electronics housing (50) and is screwed into a threaded bore of the power electronics, wherein a hollow centering dome (64), in particular made of plastic, is formed on the connecting tab (62) and projects towards the signal electronics housing (50), in particular parallel to the plug-in connection direction of the plug-in connection formed from the plug-in connector part (53) and the mating plug-in connector part (81), wherein a pin, in particular a cross pin (54), is formed on the signal electronics housing (50), which projects into the hollow centering mandrel (64), in particular for centering the signal electronics housing relative to the sheet metal housing.
2. Electrical device according to claim 1, characterized in that the connecting tab (62) on the cover (60) is formed at an angle.
3. Electrical device according to one of the preceding claims, characterized in that the cover (60) is a plastic injection-molded part.
4. Electrical device according to one of the preceding claims, characterized in that on the cover (60) formed and protruding pins (61) protrude into depressions or recesses of a base plate (67) of the electrical device, wherein the sheet metal housing is connected to the base plate (67), wherein a sheet metal edge of the sheet metal housing protrudes into a groove (66) of the cover (60), in particular wherein the sheet metal edge is pivoted into the groove (66) by a pivoting movement about the connecting line of the pins (61), in particular during assembly of the electrical device, in particular and thus protrudes.
5. Electrical device according to one of the preceding claims, characterized in that the cover (60) has a knockout area (65), in particular after its removal a screw (4) becomes accessible which secures an electrical earth connection or PE connection.
6. Electrical device according to one of the preceding claims, characterized in that the electrical device, in particular the power electronics, has a printed circuit board (3) which is equipped with a heat-generating component (6), in particular a power semiconductor, a heat sink (2) with at least one cooling fin (20) and a housing part (5) of the sheet metal housing, wherein a socket (1), in particular a press-in socket, is inserted into a recess of the cooling fin (20), wherein a screw (4), the screw head of which connects the printed circuit board (3) to the component (6) for Heat sink (2) is pressed, is screwed into an internal thread of the socket (1), wherein the socket (1) has a polygonal area (31) which is pressed into the housing part (5).
7. Electrical device according to one of the preceding claims, characterized in that the bushing (1) has a toothing which is cut into the material of the cooling fin (20).
8. Electrical device according to one of the preceding claims, characterized in that the toothing (30) is an external toothing.
9. Electrical device according to one of the preceding claims, characterized in that the screw (4) projects through the heat sink (2), in particular through the cooling fin (20).
10. Electrical device according to one of the preceding claims, characterized in that the housing part (5) is arranged on the side of the heat sink facing away from the printed circuit board (3), and / or that the printed circuit board (3) is arranged on the side of the heat sink (2) facing away from the housing part (5).
11. Electrical device according to one of the preceding claims, characterized in that the housing part (5) is made as a stamped and bent part from a sheet metal.
12. Electrical device according to one of the preceding claims, characterized in that on at least one side of the housing part, in particular on the side of the housing part facing away from the heat sink (2), the polygonal region (31) is arranged flush with the housing part (5).
13. Electrical device according to one of the preceding claims, characterized in that the polygonal region (31) on the socket (1) protrudes radially, and / or that the polygonal region (31) is spaced from the toothing (30), and / or that the recess is an interruption of the cooling fin (20), and / or that the socket (1) is made of steel, and / or that the heat sink (2) is made of aluminum.
14. Electrical device according to one of the preceding claims, characterized in that the cooling fin (20) has a thickening which is interrupted by the recess, in particular wherein the socket (1) is inserted into the recess and is thus received in the thickening.
15. Electrical device according to one of the preceding claims, characterized in that a further socket (1), in particular a further press-in socket, is inserted into a further recess of a further cooling fin (20) of the heat sink (2), wherein a further screw (4), the screw head of which presses the circuit board (3) with a further component (6) towards the heat sink (2), is screwed into an internal thread of the further socket (1), wherein the further socket (1) has a further polygonal area (31) which is also pressed into the housing part (5), wherein the further socket (1) has a further toothing (30) which is cut into the material of the further cooling fin (20), wherein the further toothing (30) is also an external toothing, wherein the further screw (4) projects through the heat sink (2), in particular through the further cooling fin (20).