Patent Application
20060256533
1. Field of the Invention
The present invention is related to printed circuit boards with heat removing components.
2. Background Art
The automobile industry is consistently driven by the need to simultaneously provide additional features while decreasing vehicle weight and costs. Moreover, the inclusion of these additional features is also limited by the amount of available space for housing such options and associated components.
It is known that the components within electronic devices generate heat that needs to be sufficiently dissipated for efficient operation. A number of cooling mechanisms are used to reduce the temperature of electrical components in such devices. Examples of passive cooling mechanisms include components such as heat sinks. In some prior art designs, vias are used to carry heat away from components. These prior art via constructions are usually open channels which lead from an electronic component mounted on a circuit board to the other side of the circuit board. Active cooling methods using fans or cooling lines are expensive and complicated. Moreover, these active methods require significant amounts of space which is at a premium in a motor vehicle.
Junction boxes are an example of an electronic device that is found in motor vehicles. These devices typically include one or more printed circuit boards having one or more electronic components mounted thereon. These electronic components include switches and drivers used to control virtually any electronic feature found in an automobile. Examples include, switches and drivers for controlling headlights, windshield wipers, turn signals, power window motors, and combinations thereof. Junction boxes are often mounted in a vehicle's passenger compartment which as explained above has limited space. The combination of increasing electrical options in vehicles and limited space challenges the current approaches used to dissipate heat in automobile junction boxes.
Accordingly, there exists a need in the prior art for improved electronic devices with either reduced sizes or with increased number of electronic components therein.
The present invention overcomes one or more problems of the prior art by providing in one embodiment an electronic device with improved heat transfer characteristics. The electronic device of this embodiment includes one or more active or passive electronic components, one or more metal coupons, and a printed circuit board. The one or more active electronic components are mounted on a first side of a printed circuit board while the one or more metal coupons are mounted on a second side of the printed circuit board. This embodiment further includes an adhesive that bonds at least a portion of the metal coupon to the second side of the printed circuit board. Advantageously, the metal coupon is adapted to simultaneously transfer heat from an electrical signal across the printed circuit board. The electronic device of the present invention is particularly useful for incorporation into a junction box, and in particularly, for incorporation into the type of junction box used in an automobile.
In another embodiment of the invention, a method of forming the electronic device set forth above is provided. The electronic device is formed from a printed circuit board having one or more vias and one or more electronic components mounted thereto. The method of this embodiment comprises forming a metal coupon into a predetermined shape followed by adhering the metal coupon to a printed circuit board. Advantageously, the electronic device includes one or more vias in communication with the one or more electronic components such that the metal coupon simultaneously transfers heat from an electrical signal across the printed circuit board.
Reference will now be made in detail to presently preferred compositions or embodiments and methods of the invention, which constitute the best modes of practicing the invention presently known to the inventors.
The term “via” as used herein means a small hole or passage in a printed circuit board that connects two sides of the circuit board or two layers of the circuit board.
With reference to
In another variation of the present embodiment, metal coupons 16, 18 are also adapted to transfer an electrical signal across the printed circuit board. An example of such an electrical signal transfer is a DC or AC power signal that provides electrical power to at least one of electronic component 30, 32, 34, 36. In this variation, metal coupons 16, 18 includes one or more metal protrusions 50, 52, 54, 56 that pass through printed circuit board 12 extending past the first side of the printed circuit board. In a refinement of this variation, one or more metal protrusions 50, 52, 54, 56 are in the shape of a blade that may function as a male connector. Optionally, one or more of metal protrusions 50, 52, 54, 56 are adjacent to shrouds 60, 62 which are used to protect the protrusion and/or to assist in the attachment of cables to the protrusions. Typically, the electronic device of the invention includes additional contact blades 70, 72, 74, 76 for attachment to other cables contacting electronic device 10. This additional cabling may be used for any purpose such as carrying control or power signals.
In another embodiment of the invention, a method of forming the electronic device set forth above is provided. With reference to
While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
