Electronic component

Abstract

Electronic assembly with a housing (18) with one open side which is closed by a component acting as a lid, a heat sink (28) through which heat can be dissipated from the housing, a printed circuit board (2) which is arranged on a contact surface (30) of the heat sink (28) in the housing and is inserted into the housing in a sliding direction (24) via the open side of the housing (18), for which a guide is formed in the housing (18), electronic circuit components (4) arranged on the printed circuit board (2), and a connector part (8) which is electrically connected to the circuit components (4) on the circuit board and attached to the circuit board (2), where the contact surface (30) of the heat sink (28) and an extension plane spanned by the circuit board (2) to the insertion direction (24) of the circuit board (2) are arranged at an angle at least immediately before contact between the circuit board (2) and the contact surface (30) when plugging in.

Description

[0001] The invention relates to an electronic component with a housing having an open side which is closed by a component acting as a cover, a heat sink through which heat can be dissipated from the housing, a printed circuit board which is arranged on a contact surface of the heat sink in the housing and is inserted into the housing through the open side of the housing, electronic circuit components which are arranged on the printed circuit board and a connector which is electrically connected to the circuit components on the printed circuit board.

[0002] These types of electronic components are used in a wide variety of applications. They can be used as control devices for pumps, actuators, or other electrically driven components. The heat sink serves to dissipate heat from the housing, which is generated particularly in the power components of the unit and can lead to overheating of the electronic components.

[0003] Electronic components are particularly well-known whose housings are open at the top, allowing the circuit board to be inserted into the housing in the direction of a normal to the plane spanned by the circuit board.

[0004] Such an electronic device is known, for example, from EP 1 006 766 A2. This patent describes an electrical control unit for motor vehicles in which a printed circuit board (PCB) is attached to a heat sink by means of screws. The heat sink is part of a housing surrounding the PCB and closed by a lid. The PCB is inserted into the housing from the side closed by the lid and screwed to the heat sink. A connector is integrally formed with the housing and has contact pins that protrude into corresponding openings in the PCB when it is inserted and must be soldered there. However, such subsequent soldering can lead to contact errors.

[0005] This disadvantage is avoided by a control device as disclosed in DE 199 55 589 A1. This document describes an electronic control device in which a connector part is attached laterally to a printed circuit board and inserted into a housing from the side along with the board. A guide structure is provided in the housing for this purpose. How a tight seal between the housing and the connector can be achieved after insertion is not disclosed. Furthermore, this arrangement does not allow for sufficient contact with a heat sink, as the board would be inserted parallel to the heat sink and would therefore have to slide along the cooling surface during insertion. This could, however, lead to damage to the electrical contacts and conductor tracks. Additionally, any contact adhesive applied to the cooling surface or the board would be smeared uncontrollably during lateral insertion.

[0006] Furthermore, an electronic control unit is known from DE 25 30 157 A1, which has a housing with a base and four side walls. Two domes extend from the base, the surfaces of which are inclined, and a bearing plate is attached inclined to these surfaces. A circuit board with circuit components, spaced apart from the bearing plate, is arranged parallel to the bearing plate. One of the side walls has an opening through which a connector protrudes, which is connected to a terminal strip on which the circuit board is attached. The housing is closed by a lid. Sufficient cooling is not provided.

[0007] The task therefore is to provide an electronic component that ensures sufficient heat dissipation into the housing environment and simultaneously allows the connector part to be pre-assembled on the circuit board and plugged into the housing together with it.

[0008] This problem is solved by an electronic component with the features of the characterizing part of the main claim.

[0009] Because the contact surface of the heat sink and an extension plane spanned by the circuit board are arranged at an angle to the insertion direction of the circuit board, at least immediately before contact between the circuit board and the contact surface, good contact between the circuit board and the heat sink can be achieved, thus significantly increasing heat transfer to the housing environment, since there is a straight contact without shearing motion between the circuit board and the contact surface.

[0010] By attaching the connector part to the circuit board and allowing the circuit board to be inserted into the housing from the open side against the contact surface of the heat sink, pre-assembly of the connector part on the board is simultaneously made possible, which significantly simplifies assembly and reduces sealing surfaces, as lateral insertion becomes possible.

[0011] In a preferred embodiment, the connector part has a plate extending perpendicular to the contact pins of the connector part, which acts as a cover for closing the open side of the housing, wherein the plate is arranged at an angle between 45° and 85° to the circuit board. Thus, the housing can be closed without additional components simply by inserting the circuit board with the connector part and the plate.

[0012] Preferably, an adhesive or paste is applied between the contact surface of the heat sink and the printed circuit board. This ensures, on the one hand, that the printed circuit board is fixed to the heat sink and, on the other hand, that the thermal conductivity from the printed circuit board to the heat sink is improved by the large-area, firm bond at high thermal conductivity coefficients.

[0013] Furthermore, it is advantageous to position circuit components for improving electromagnetic compatibility in the connector area on the side of the circuit board opposite the heat sink. These components are typically relatively large. However, the required installation space does not need to be increased because, with the angled circuit board, these components are located in an area where more space is available within the housing. Additionally, the effectiveness of these components in improving electromagnetic compatibility in the connector area is enhanced.

[0014] In a further development, the housing can have openings on its side opposite the heat sink, which can be closed with covers featuring circumferential seals. These can be used, for example, to provide access to programming interfaces on the circuit board surface.

[0015] In a particularly preferred embodiment of the invention, the circuit board and the connector part are attached to a frame. This frame serves to fix the position of the circuit board relative to the connector part and this assembly within the housing, thereby simplifying assembly and reducing the mechanical stress on the circuit board and the electrical connections to the connector part during insertion.

[0016] Preferably, the connector part and the frame are manufactured in one piece using injection molding, which further simplifies manufacturing and assembly and eliminates tolerance errors caused by inaccurate positioning of the individual parts relative to each other.

[0017] In a further development, the plate serving as a cover is also part of the frame, thus eliminating further manufacturing and assembly steps.

[0018] Furthermore, it is advantageous to incorporate a guide within the housing, allowing the frame to be slid into place. This reliably prevents the circuit board or frame from jamming or tilting during assembly. It also ensures precise positioning.

[0019] Preferably, the circuit board is clipped into the frame. This is a particularly simple and reliable method of attachment, which is also very easy to perform.

[0020] Furthermore, a die-cut grid is advantageously formed within the frame, which contains the contact pins of the connector part as well as their electrical contacts to the circuit board. This further simplifies the manufacturing process of the assembly, as routing the wires and subsequent contacting are no longer necessary.

[0021] To further simplify sealing the housing's interior from its exterior, a circumferential seal is attached to the frame. This creates a seal on the open side of the housing when the unit, consisting of a plate, connector, and circuit board, is inserted.

[0022] This creates an electronic component that is protected against overheating, as a reliable connection of the thermally stressed circuit board to the heat sink is ensured, and at the same time is easy to assemble, as the connector part can be pre-assembled on the circuit board.

[0023] An embodiment of an electronic component according to the invention is shown in the figures and is described below. Fig. Figure 1 shows a schematic side view of an electronic component according to the invention. Fig. Figure 2 shows a side view of a pre-assembled unit of the electronic assembly. Fig. 1 in schematic representation. Fig. Figure 3 shows a side view of a frame with connector part of the electronic assembly. Fig. 1 in schematic representation.

[0024] The electronic assembly according to the invention consists of a printed circuit board 2 on which electronic circuit components 4 are arranged. The circuit components 4 are electrically connected via lines (not shown) on the printed circuit board 2 and a die-cut grid 6 to a connector part 8, wherein the end pieces of the die-cut grid 6 projecting from the connector part 8 serve as contact pins 10 for a corresponding connector part.

[0025] The punch grids 6 are, as in Fig. As can be seen in Figure 3, the connector part 8 is fixedly arranged in a frame 12, which is made of plastic and is manufactured, for example, by injection molding after the die-cut grids 6 are placed in a corresponding mold. The connector part 8 is also manufactured in one piece with the frame 12. Perpendicular to the contact pins 10 of the connector part 8, a plate 14 extends on the frame 12 directly behind the connector part 8. On the side of the plate 14 opposite the connector part 8 is a circumferential seal 16, which, after the frame 12 is installed in a substantially cuboid housing 18, rests against the walls 20 of the housing 18 from the inside, while in this assembled state the plate 14 rests against the ends of the walls 20 of the housing 18 that define one open side 22 and acts there as a cover.

[0026] The frame 12 further has a mounting plane for the circuit board 2, which, in the installed state of the circuit board 2, corresponds to a plane of extension of the circuit board 2 and is arranged at an angle of approximately 15-20° to the direction of extension of the contact pins 10 in the connector part 8, or at an angle of approximately 70-75° to the plate 14. The direction of extension of the contact pins 10 in the connector part 8 corresponds in this case to an arrow pointing in Fig. 1 shown insertion direction 24 of the frame 12 or the circuit board 2 into the housing 18.

[0027] The circuit board 2 is attached to the frame 12 by means of a clip connection. This is achieved via locking tabs 26 formed on the frame 12. When the circuit board 2 snaps into place under the locking tabs 26, contact is also made between the circuit board 2 and the die-cut grid 6.

[0028] As already mentioned, the frame 12 with the attached circuit board 2 is inserted into a housing 18 from the open side 22. A finned heat sink 28, preferably made of a highly thermally conductive metal, is arranged on this housing 18. This heat sink 28 has a contact surface 30 which is angled to the ends of the walls 20 that define the open side 22 of the housing 18 at the same angle as the circuit board 2 is angled to the cover plate 14. It follows that, in its final position, the circuit board 2 rests flat on the contact surface 30 of the heat sink 28, with the electronic circuit components 4 arranged on the side of the circuit board 2 opposite the heat sink 28. However, this contact is only established immediately before the circuit board 2 reaches its final position on the contact surface 30 when the frame 12 is inserted. Fig.Figure 1 shows this final position. In addition to the open side 22, from which the frame 12 can be inserted into the housing 18, the housing 18 has a further opening 32 on its side opposite the heat sink 28, through which any programming interfaces on the circuit board 2 remain accessible even after installation. This opening is closed by a cover 34 with a circumferential seal 36 in between.

[0029] The manufacturing and assembly process begins with the assembly of the printed circuit board 2, which is populated with electronic circuit components 4 and circuit components 38 to improve electromagnetic compatibility. The frame 12, including the die-cut grid 6, the plate 14, and the connector part 8, is then injection-molded. The seal 16 can subsequently be either injection-molded or inserted. Sealing by adhesive bonding is also possible.

[0030] The circuit board 2 is clipped into the frame 12 in such a way that contact is made with the stamped grid 6. The circuit components 38, which typically require a relatively large installation space, are located in the area directly behind the connector part 8. This ensures that, despite the angle of the circuit board 2 towards the subsequent insertion direction 24, they do not protrude beyond the outer dimensions of the frame 12. The circuit board 2 can also be additionally connected to the frame 12 via selective solder joints.

[0031] Subsequently, an adhesive 40 or a paste with a high thermal conductivity coefficient is applied to the side of the circuit board 2 opposite the circuit components 4, 38.

[0032] The frame 12 with the circuit board 2 is then inserted into the housing 18 from the open side 22 in the insertion direction 24. For this purpose, a guide (not shown) is formed in the housing 18, which can, for example, be in the form of a groove extending in the insertion direction and corresponding to a projection on the frame 12. The insertion continues until contact is simultaneously established between the underside of the circuit board 2, on which the adhesive 40 is applied, and the contact surface 30 of the heat sink 28, as well as between the board 14 and the ends of the walls 20. This state corresponds to the final position of the frame 12 in the housing 18. In this final position, the contact between the circuit board 2 and the heat sink 28 creates an adhesive force of the adhesive 40, so that a thermally conductive, solid connection is formed between the heat sink 28 and the circuit board 2.Simultaneously, the seal 16 rests against the walls 20 from the inside, creating a seal in this direction between an inner 42 of the housing and an outer one. The plate 14 can be screwed to the housing 18 for further fastening of the frame 12 inside the housing 18. Additionally, a screw connection between the circuit board 2 and the heat sink 28 can also be made via the opening 32. After the seal 36 is inserted around the opening 32, it is closed by the cover 34, which can also be fastened with screws.

[0033] This electronic assembly features excellent thermal contact between the heat-generating circuit components, 4, 38, and the heat sink, thus largely preventing damage to the circuit due to thermal overload. This is ensured by the simultaneous assembly of the tightly designed and pre-assembled connector section, as the angled arrangement and design of the heat sink and the circuit board result in delayed contact between the two components, even when inserted laterally. According to the invention, the angled arrangement of the circuit board and the contact surface relative to the insertion direction prevents shearing between the contact surface of the heat sink and the circuit board. This assembly is easy to manufacture and assemble.

[0034] It should be clear that various design modifications are conceivable within the scope of protection of the main claim compared to the described embodiment. In particular, the arrangement of the housing openings, the design of the circuit board, or its connection to the connector part can be implemented in different ways. The angle of inclination can also be selected differently. Furthermore, the circuit board and the contact surface could be arranged essentially perpendicular to the cover, provided that the last section when the circuit board is inserted is again arranged at an angle to the contact surface, thus preventing the shearing off of previously applied contact paste.

Claims

[1] Electronic assembly with a housing (18) with one open side which is closed by a component acting as a lid, a heat sink (28) through which heat can be dissipated from the housing, a printed circuit board (2) which is arranged on a contact surface (30) of the heat sink (28) in the housing and is inserted into the housing in a sliding direction (24) via the open side of the housing (18), for which a guide is formed in the housing (18), electronic circuit components (4) arranged on the printed circuit board (2), and a connector part (8) which is electrically connected to the circuit components (4) on the circuit board and attached to the circuit board (2), where the contact surface (30) of the heat sink (28) and an extension plane spanned by the circuit board (2) to the insertion direction (24) of the circuit board (2) are arranged at an angle at least immediately before contact between the circuit board (2) and the contact surface (30) when plugging in. [2] Electronic component according to claim 1, characterized by , that the connector part (8) is attached to the circuit board (2) and can be inserted with the circuit board (2) from the open side (22) of the housing (18) into the housing (18) against the contact surface (30) of the heat sink (28). [3] Electronic component according to any one of the preceding claims, characterized by, that the connector part (8) has a plate (14) extending perpendicular to the contact pins (10) of the connector part (8), which is the component acting as a cover for closing the open side (22) of the housing (18), wherein the plate (14) is arranged at an angle between 45° and 85° to the circuit board (2). [4] Electronic component according to any one of the preceding claims, characterized by , that an adhesive (40) or a paste is arranged between the contact surface (30) of the heat sink (28) and the circuit board (2). [5] Electronic component according to any one of the preceding claims, characterized by , that circuit components (38) are arranged on the side of the circuit board (2) opposite the heat sink (28) in the area of ​​the connector part (8) to improve electromagnetic compatibility. [6] Electronic component according to any one of the preceding claims, characterized by, that the housing (18) has an opening (32) on its side opposite the heat sink (28), which can be closed by means of a cover (34) with circumferential seals (36). [7] Electronic component according to any one of the preceding claims, characterized by , that the circuit board (2) and the connector part (8) are attached to a frame (12). [8] Electronic component according to any one of claims 1 to 6, characterized by , that the plug part (8) and the frame (12) are manufactured in one piece using the injection molding process. [9] Electronic component according to one of claims 7 or 8, characterized by , that the plate (14) serving as a cover is part of the frame (12). [10] Electronic component according to any one of claims 7 to 9, characterized by , that a guide is formed in the housing (18) via which the frame (12) can be inserted into the housing (18). [11] Electronic component according to any one of claims 7 to 10, characterized by , that the circuit board (2) is clipped into the frame (12). [12] Electronic component according to any one of claims 7 to 11, characterized by , that in the frame (12) a stamped grid (6) is formed which contains the contact pins (10) of the connector part (8) as well as their electrical contacts to the circuit board (2). [13] Electronic component according to any one of claims 7 to 12, characterized by , that a circumferential seal (16) is attached to the frame (12), through which the interior (42) of the housing (18) is sealed to the exterior.

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