Electricity: electrical systems and devices – Housing or mounting assemblies with diverse electrical... – For electronic systems and devices
Reexamination Certificate
2002-10-11
2004-06-29
Vortman, Anatoly (Department: 2835)
Electricity: electrical systems and devices
Housing or mounting assemblies with diverse electrical...
For electronic systems and devices
C361S705000
Reexamination Certificate
active
06757171
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates to a device for fixing a heat distribution covering on a printed circuit board having a plurality of heat-generating electronic components arranged on a placement area of the printed circuit board.
Heat distribution coverings of this type serve to take up the heat from the heat-generating electronic components and to distribute the heat energy over a relatively large cooling area. However, the fixing of a heat distribution covering of this type constitutes a problem since corresponding fixing elements on the one hand occupy part of the placement area and on the other hand impair the strength of the printed circuit board. Furthermore, the area losses arising as a result of each fixing element multiply, in the case of a multilayer printed circuit board, with the number of conduction planes provided.
SUMMARY OF THE INVENTION
It is accordingly an object of the invention to provide an improved device for fixing a heat distribution covering, which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and further a circuit board provided with a heat distribution covering that is attached with the improved device.
With the foregoing and other objects in view there is provided, in accordance with the invention, a device for fixing a heat distribution covering on a printed circuit board. The printed circuit board (PCB) has a placement area carrying a plurality of heat-generating electronic components and at least one conductor track plane for connecting to contact terminals of the components. The fixing device comprises:
a fixing foot attached on the placement area above at least one further conductor track plane extending below the fixing foot; and
a fixing element disposed on the fixing foot and configured to engage and hold the heat distribution covering on the printed circuit board.
Specifically, the fixing foot is disposed to be aligned opposite an opening formed in the heat distribution covering.
In other words, the invention provides for a device for fixing a heat distribution covering on a printed circuit board with a plurality of heat-generating electronic components arranged on a placement area of the printed circuit board and has at least one conductor track plane for interconnecting contact connections of the components.
In a region on the placement area which has at least one fixing foot, the fixing foot bears a placement element. The placement element can be brought into engagement with the heat distribution covering and at least one further conductor track plane is arranged below the region of the fixing foot.
This type of fixing has the advantage that it is only for the at least one fixing foot on the placement area of the printed circuit board that a corresponding metallic layer, of which the conductor tracks are also composed, has to be uncovered in order to arrange and fix the fixing foot on this metallic area. There is no need to fit further mechanical clamping or fixing devices through the printed circuit board itself, so that, in particular, in the case of multilayer printed circuit boards, conductor track planes lying below the region which is occupied by the fixing foot are available with no loss of area for the conductor track routing. Consequently, the device according to the invention provides the possibility of exhausting the full volume of the printed circuit board for the conductor track connections and limits the area requirement on the printed circuit board only to the fixing area required for at least one fixing foot on the topmost conductor track plane of the printed circuit board.
In accordance with an added feature of the invention, the device has a soldered connection between the fixing foot and the placement area, the soldered connection having the advantage that it can be combined temporarily with soldering connecting steps for fitting the electronic components, thereby obviating additional processing steps.
In accordance with an additional feature of the invention, the device has a friction welding connection between the fixing foot and the placement area. The friction welding connection has the advantage that it is only locally in the region of the fixing foot that the printed circuit board is heated during the production of the connection and the induction of thermoelectric voltage in the printed circuit board is reduced compared with a soldered connection.
Furthermore, the device may have an adhesive bonding between the fixing foot and the placement area. Since an adhesive bonding connection can be realized without a temperature increase in this case, a thermally nonstressed connection results, which is advantageous in many applications.
In accordance with another feature of the invention, the heat distribution covering has an opening arranged opposite the fixing foot. This embodiment is associated with the advantage that fixing elements can be inserted through the opening arranged opposite the fixing foot and can thus bring the heat distribution covering into engagement with the fixing foot.
To that end, in one embodiment of the invention, the fixing element may be a threaded pin applied orthogonally to the placement area on the fixing foot. A fitting nut can be screwed onto a thread pin of this type, the nut being arranged with an accurate fit in the opening in the heat distribution covering, so that the heat distribution covering is in engagement with the fixing foot via the threaded pin with the aid of the fitting nut reaching through the opening. This results in a releasable fixedly anchored fitting of the heat distribution covering on the printed circuit board.
In a further embodiment of the invention, heat-generating components on the printed circuit board whose structural height is smaller than the distance between heat distribution covering and printed circuit board are thermally conductively connected to the heat distribution covering by means of a heat-conducting filling material which is arranged between the individual electronic component and the heat distribution covering. This embodiment of the invention has the advantage that a wide variety of heat-generating components with varying structural height can be cooled by the heat distribution covering by means of the heat-conducting filling material.
Instead of a threaded pin applied orthogonally to the placement area on the fixing foot, it is also possible to arrange a fixing element with an internal thread, such as a fixing nut, on the fixing foot. In this case, the heat distribution covering is screwed to the internal thread of the fixing element with the aid of a covering screw which projects through the opening in the heat distribution covering. Both a fixing nut and a threaded pin may be formed in one piece with the fixing foot, thereby reducing the number of components to be stored for the fixing according to the invention.
In a further embodiment of the invention, the fixing element is a plug pin with an attachment via which a plug element arranged with an accurate fit in the opening in the heat distribution covering is in engagement. A plug element of this type may have, in the region of the attachment of the plug pin, snap-action hooks which slide over the attachment and spread apart and then latch into place behind the attachment, so that the heat distribution covering is fixedly connected to the fixing foot and thus to the printed circuit board via the plug element and the plug pin. The plug pin and the fixing foot may be formed in one piece, which again affords the advantage that the number of fixing elements to be stored is reduced.
In a further embodiment of the invention, the fixing element is a cylindrical wherein is arranged orthogonally to the placement area of the printed circuit board on the fixing foot or is formed in one piece with the fixing foot. A cylindrical pin of this type as fixing element may project through the opening in the heat distribution covering and the heat distribution covering may be fixed at the cylindrical pin
Bauer Monika
Pohl Jens
Greenberg Laurence A.
Infineon - Technologies AG
Mayback Gregory L.
Stemer Werner H.
Vortman Anatoly
LandOfFree
Device for fixing a heat distribution covering on a printed... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for fixing a heat distribution covering on a printed..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for fixing a heat distribution covering on a printed... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3364953