control unit

Abstract

The invention relates to a control device (10) with a housing (12) which has a lower housing part (24) and a upper housing part (14) which form an interior space (38) for receiving a printed circuit board (36), with fastening domes (34) formed monolithically on the lower housing part (24), with supports (44) formed on the fastening domes (34) for at least indirectly supporting the printed circuit board (36) in the direction of the lower housing part (24), with at least one heat-generating component (46) arranged on the printed circuit board (36) which is thermally coupled to the upper housing part (14) by means of a heat-conducting medium (50), wherein the lower housing part (24) is designed as an injection-molded part made of plastic, and the upper housing part (14) is designed from metal.

Description

Technical FieldThe invention relates to a control unit which is distinguished by a particularly advantageous dissipation of heat of at least one heat-generating component to the environment with a relatively simple structural design and simple assembly of the control unit.Prior ArtDE 10 2011 121 576 A1 discloses a control device with a housing which has a housing cover made of metal. The housing cover is positioned in contact with a printed circuit board via a thermally conductive filling material in order to enable heat dissipation of heat-generating components of the printed circuit board. A housing trough covers the housing cover and, together with the housing cover, forms an interior for receiving the printed circuit board. The fastening between the housing cover and the housing trough takes place in a peripheral region of the housing trough by means of adhesive which is arranged in a groove-like depression of the housing cover, into which depression the peripheral region of the housing trough dips.DE 10 2015 007 074 A1 discloses a shielding housing for printed circuit boards, which has a heat dissipation function. Formed on the shielding housing are deformable tabs which can position and fix a printed circuit board in a tolerance-compensating manner.Finally, it is known from DE 10 2013 206 999 A1 of the applicant to form an embossing in a thermally conductive cover of a housing of a control device, which embossing reduces a distance from a heat-generating component, wherein the component is connected to the component in a thermally conductive manner in the region of the embossing.Disclosure of the InventionThe control device according to the invention having the features of claim 1 has the advantage that, on the one hand, it can bridge gaps, which are caused by tolerances, between heat-generating components and the housing cover of the housing in a particularly simple manner and at the same time thermally connects the heat-generating components to the housing cover, and, on the other hand, the housing can be closed in a particularly simple manner without separate connecting elements, solely by the geometric configuration of the housing components.Against the background of the above explanations, a control device according to the invention having the features of claim 1 therefore has a housing which consists of a lower housing part and an upper housing part which form an interior for receiving a printed circuit board. Monolithically formed fastening domes are provided on the housing lower part, wherein supports formed on the fastening domes serve for at least indirectly supporting the circuit board in the direction of the housing lower part. Furthermore, the printed circuit board has at least one heat-generating component which is arranged on the printed circuit board and is thermally coupled to the upper housing part by means of a heat-conducting means. The lower housing part is formed as an injection-molded part made of plastic, and the upper housing part is formed from metal. The upper housing part has first side walls which pass through through openings formed in the lower housing part in alignment with the first side walls, at least in sections. Furthermore, holding sections are provided on the first side walls, which project beyond a housing base of the housing lower part, and which are shaped in the direction of the housing base and abut against the housing base in order to fix the housing upper part to the housing lower part.Advantageous refinements of the control unit according to the invention are listed in the dependent claims.It is preferably provided that the holding sections are designed as fastening tabs which have a smaller lateral extent than the first side walls. As a result, with saving material or low weight, a relatively low deformation force is required in order to form the holding sections against the housing base.Furthermore, it can be provided that the holding sections bear against the housing base only with end sections. As a result, a spring effect between the upper housing part and the lower housing part can be achieved by the holding sections, which can serve for the tolerance compensation.In a structurally preferred embodiment, it is furthermore provided that the through-openings are formed in the housing lower part between two second side walls arranged parallel to one another, and that the second side walls are connected to one another by intermediate webs.Furthermore, in a preferred development of the last proposal, it is provided that the first side walls of the upper housing part have groove-shaped recesses in which the intermediate webs are arranged.For simple fixing of the printed circuit board in the interior of the housing, it can furthermore be provided that the fastening domes penetrate through openings on the printed circuit board and are formed deformed in a heat-sealed manner against an upper side of the printed circuit board.It is furthermore preferred if both the upper housing part and the lower housing part are designed in the form of a trough. As a result, only two housing components are required for forming the housing.A heat-conducting adhesive or similar medium is particularly suitable as heat-conducting means. Such a heat conducting means has the advantage that it can very easily compensate tolerance-related differences in the size of the gap between the upper side of the component and the upper housing part.It is furthermore preferred if the control device is designed as a gateway control device for a vehicle.Further advantages, features and details of the invention are evident from the following description of preferred embodiments of the invention and on the basis of the drawings.Brief Description of the DrawingsFIG. 1 shows a partial area of a control device according to the invention in a longitudinal section before fixing an upper housing part to a lower housing part, FIG. 2 is a sectional view taken along the line II--II of FIG. 1; and FIG. 3 shows a section through the control device according to FIG. 1 with the upper housing part fixed.Embodiments of the InventionIdentical elements or elements with the same function are provided with the same reference numbers in the figures.FIG. 1 shows a partial area of a control unit 10 which preferably, but not by way of limitation, serves as a gateway control unit 100 for a vehicle or is designed for this purpose. The control device 10 has a cubic housing 12 which is formed in multiple parts, in particular in two parts. The housing 12 comprises an upper housing part 14 consisting of metal, in particular of aluminum, which is preferably designed as a sheet metal part. The upper housing part 14 forms a housing cover 16, from which first side walls 18 project perpendicularly. On the side facing away from the housing cover 16, the first side walls 18 each have holding sections 19 in the form of fastening lugs 20 which are formed monolithically with the first side walls 18.Depending on the length of the first side walls 18, at least one holding section 19 is provided on each of the four first side walls 18. The lateral extent of the holding sections 19 running perpendicular to the plane of the drawing of FIG. 1 is smaller than the sections of the first side walls 18 facing the housing cover 16, which extend along the entire edges of the housing cover 16 in each case.In each case, groove-shaped recesses 22 are formed on the holding sections 19, which recesses extend as far as into the region of the first side walls 18 (FIG. 2 ).Furthermore, the housing 12 has a housing lower part 24 which is produced from plastic, in particular by injection molding. The lower housing part 24 forms a housing base 26 from which two second side walls 28, 30 arranged parallel to one another protrude on the edge side, between which a through-opening 31 is formed in each case. In analogy to the first side walls 18, only two second side walls 28, 30 can be seen in FIG. 1. In the exemplary embodiment shown, the first side walls 18 of the upper housing part 14 extend over the entire height of the two second side walls 28, 30 and slightly beyond it.In order to connect the second side walls 28, 30 of the housing lower part 24 to one another, intermediate webs 32 that can only be seen in FIG. 2 are arranged between two second side walls 28, 30. The intermediate webs 32 are adapted to the cross section or the groove width of the recesses 22 in such a way that the intermediate webs 32 are preferably arranged in the recesses 22 with only slight play. Furthermore, the intermediate webs 32 form a stop for the recesses 32, which rest with their groove base against the intermediate webs 32 in order to limit the movement of the upper housing part 14 to the lower housing part 24 (FIG. 2 ).It is additionally mentioned that in the exemplary embodiment shown, the recesses 22 are located in the region of the holding sections 19. It is of course also possible alternatively or additionally to provide such recesses 22 in the region of the first side walls 18 laterally next to the holding sections 19.Fastening domes 34 protrude from the housing base 26 of the housing lower part 24, which serve for fixing or positioning a printed circuit board 36 in an interior 38 of the housing 12 formed by the housing lower part 24 and the housing upper part 14. The pin-shaped fastening domes 34 pass through passage openings 42 of the printed circuit board 36 with a section 40 of reduced diameter. Preferably, four fastening domes 34 and passage openings 42 are preferably provided at corner regions of the printed circuit board 36. In the transition region to the sections 40, the fastening domes 34 form supports 44 for the printed circuit board 36 in order to position the printed circuit board 36 in the interior 38.On the side of the printed circuit board 36 facing the housing cover 16, the fastening domes 34 project beyond the printed circuit board 36 and are formed deformed in the shape of a rivet head by hot caulking against the upper side of the printed circuit board 36 in order to form a fixing of the printed circuit board 36 on the fastening domes 34.On the upper side of the printed circuit board 36 facing the upper housing part 14 or the housing cover 16, at least one heat-generating component 46, in particular an IC 48, is furthermore arranged. The upper side of the heat-generating component 46 is thermally coupled to the housing cover 16 via a heat-conducting means 50 in the form of a heat adhesive 52.For mounting the housing 12 or the control unit 10, the printed circuit board 36 provided with the heat-generating component 46 is first connected to the lower housing part 24 via the fastening domes 34. Subsequently, the heat conducting means 50 is preferably applied to the upper side of the heat generating component 46. The upper housing part 14 is then connected to the lower housing part 24 in such a way that the first side walls 18 of the upper housing part 14 pass through between the second side walls 28, 30 of the lower housing part 24 in the region of the passage openings 31, wherein they are guided over the intermediate webs 32. As soon as the upper housing part 14 has its end position relative to the lower housing part 24, in which the heat conducting means 50 is furthermore arranged in contact with the housing cover 16, the fastening tabs 20 are folded or formed against the housing base 26 in such a way that the fastening tabs 20 are arranged with their end sections 54 in contact with the housing base 26.The control device 10 or the housing 12 described thus far can be modified or modified in a variety of ways without departing from the inventive idea.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedDE 10 2011 121 576 A1

[0002] DE 10 2015 007 074 A1

[0003] DE 10 2013 206 999 A1

[0004]

Claims

Control device (10), having a housing (12) which has a housing lower part (24) and a housing upper part (14) which form an interior space (38) for receiving a printed circuit board (36), having fastening domes (34) which are monolithically formed on the housing lower part (24), having supports (44) which are formed on the fastening domes (34) and are intended for at least indirectly bearing printed circuit board (36) in the direction of the housing lower part (24), having at least one heat-generating component (46) which is arranged on the printed circuit board (36) and is thermally coupled to the housing upper part (14) by means of a heat-conducting means (50), the housing lower part (24) being formed as an injection-molded part consisting of plastic, and the housing upper part (14) being formed from metal, the housing upper part (14) having first side walls (18), the passage openings (31) formed in alignment with the first side walls (18) in the housing lower part (24) pass through at least in sections, and with holding sections (19) on the first side walls (18) which project beyond a housing base (26) of the housing lower part (24) and are shaped in the direction of the housing base (26) and abut against the housing base (26) in order to fix the housing upper part (14) to the housing lower part (24).Control device according to Claim 1, characterized in that the retaining portions (19) are designed as fastening lugs (20) which have a smaller lateral extent than the first side walls (18).Control device according to Claim 1 or 2, characterized in that the holding sections (19) bear against the housing base (26) only by end sections (54).Control device according to Claim 2 or 3, characterized in that the through-openings (31) in the housing lower part (24) are formed between two second side walls (28, 30) of the housing lower part (24) which are arranged parallel to one another, and in that the second side walls (28, 30) are connected to one another by intermediate webs (32).Control device according to Claim 4, characterized in that the first side walls (18) of the upper housing part (14) have groove-shaped recesses (22), in which the intermediate webs (32) are arranged.Control device according to one of Claims 1 to 5, characterized in that the fastening domes (34) pass through passage openings (42) on the printed circuit board (36) and are designed to be deformed in a heat-sealed manner with respect to an upper side of the printed circuit board (36).Control device according to one of Claims 1 to 6, characterized in that the lower housing part (24) and the upper housing part (14) are of trough-shaped design.Control device according to one of Claims 1 to 7, characterized in that the upper housing part (14) is designed as a sheet metal part.Control device according to one of Claims 1 to 8, characterized in that the heat-conducting means (50) is a heat-conducting adhesive (52).Control device according to one of Claims 1 to 9, characterized in that the control device (10) is designed as a gateway control device (100) for a vehicle.

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