Patent Application
20100203771
The field of the disclosure relates generally to electronic components, and more particularly, to coaxial interconnects for use in electrically coupling a plurality of devices.
The continued reduction in size of radio frequency (RF) and other electrical components creates a need for compact RF connections that meet both electrical and mechanical requirements. Some known applications require an RF interconnection between adjacent components, and more specifically between two circuit boards. The adjacent components may be substrates or circuit boards comprising layers in a stacked assembly. Such known connectors suitable for RF connections may also be suitable for digital and other low frequency signals.
RF interconnects may be used to connect a mating portion of one component to a corresponding mating portion of another component. The corresponding mating portions may comprise elements of a grid pattern of one or both components. Some known interconnects may use compressed wire bundle interconnect structures that are available with internal pins for DC and low frequency signals. However, conventional techniques of receiving the pin typically require the pin itself to have a larger diameter than that of the wire bundle contact. Also, epoxies may be used to hold the pin and dielectric elements of the interconnect structure together. The combination of all these process steps makes the objectives of maintaining control and uniform impedance at super high frequencies difficult if not impossible. Additionally, some other known coaxial connectors typically employ a barb machined onto the pin to hold it in place within the dielectric. However the outer conductor must be modified using complex machining to maintain good impedance control.
In one aspect, an electrical interconnect system is provided. The system includes a first circuit board that includes at least one via, and a conductor configured to transmit an electrical current therethrough. The conductor includes a first signal contact extending from a conductor first end, and a dielectric cylinder configured to receive the conductor therethrough. The dielectric cylinder includes a first bellows element extending from a first end of the dielectric cylinder that is positioned adjacent to the first signal contact. The first bellows element and the dielectric cylinder are configured to form a substantially continuous outer conductor, wherein the conductor and the first bellows are configured to electrically interface to the via and maintain connection thereto using a biasing force.
In yet another aspect, an electrical interconnect device is provided. The electrical interconnect device includes a conductor configured to transmit an electrical current therethrough, wherein the conductor includes a first signal contact extending from a conductor first end. The electrical interconnect device includes a dielectric cylinder configured to receive the conductor therethrough, wherein the dielectric cylinder includes a first bellows element extending from a first end of said dielectric cylinder and positioned adjacent said first signal contact. The first bellows element and the dielectric cylinder are configured to form a substantially continuous outer conductor, and to electrically interface to the via and maintain connection thereto using a biasing force.
In yet another aspect, a method for coupling two circuits is provided. The method includes providing an electrical conductor configured to transmit an electrical current therethrough, wherein the conductor includes a first signal contact extending from a conductor first end and extending the electrical conductor within a dielectric cylinder such that the dielectric conductor substantially circumscribes the electrical conductor. The method includes extending a first bellows element from a first end of the dielectric cylinder such that a substantially continuous outer conductor is formed between the first bellows element and the dielectric cylinder and such that the first bellows element is positioned adjacent to the first signal contact and forms a compressible interface therewith. The method includes positioning the electrical conductor between a first and second circuit, wherein the conductor and the first bellows are configured to electrically interface to a circuit board via.
Non-limiting and non-exhaustive embodiments are described with reference to the following figures, wherein like reference numerals refer to like parts throughout the various views unless otherwise specified.
Referring more particularly to the drawings, embodiments of the disclosure may be described in the context of a vehicle 100 as shown in
As shown in
In the exemplary embodiment, RF interconnect 200 includes a dielectric insulating shield 230 that is positioned externally about and at least partially circumscribes coaxial cable 212. Shield 230 extends a length L2 over coaxial cable length L1, wherein in the exemplary embodiment, L2 is less than L1. Shield 230 includes a first bellows element 232 coupled to a first end 234 of shield 230 that extends outward therefrom and that is positioned adjacent to first signal contact 218. Shield 230 includes a second bellows element 236 coupled to a second end 238 of shield 230 that extends outward therefrom and that is positioned adjacent to second signal contact 222. In the exemplary embodiment, first bellows element 232 and second bellows element 236 are fabricated from a conducting metal, such as for example, aluminum, gold, silver or copper, or any conductive metal that enables RF interconnect 200 to function as described herein. Bellows elements 232 and 236 are positioned on respective first and second ends 234 and 238 of shield 230 such that a substantially continuous dielectric cylinder 240, shown in
Referring to
RF interconnect 200 may vary in length while maintaining RF performance over a range of compression. In the exemplary embodiment, L1 represents a gap measuring approximately 0.8 inches, and RF interconnect allows a total compression inward of approximately 0.050 inches, or approximately a 6.25% range of compression from coaxial cable length L1. Alternatively, RF interconnect may allow any range of compression that enables circuit boards 214 and 216 to function as described herein.
In the exemplary embodiment, a first bellows element is extended 350 from a first end of the dielectric cylinder such that a substantially continuous outer conductor is formed between the first bellows element and the dielectric cylinder, and such that the first bellows element is positioned adjacent to the first signal contact and forms a compressible interface therewith. Furthermore and in the exemplary embodiment, method 300 includes extending 360 a second bellows element from a second end of the dielectric cylinder such that a substantially continuous outer conductor is formed between the second bellows element and the dielectric cylinder and such that the second bellows element is positioned adjacent to the second signal contact and forms a compressible interface therewith. More specifically, extending 350 a first and extending 360 a second bellows element further includes fabricating the first and the second bellows element from a dielectric material that is configured to compress under an inward load and provide a biasing force to maintain respective first and second conductors in contact with the circuit board via.
Method 300 includes positioning 370 the electrical conductor between first and second circuits, wherein the conductor and the first bellows are configured to electrically interface to a circuit board via. Positioning 370 the electrical conductor between a first and second circuit further includes maintaining a substantially constant electrical current flow between the first and second circuit board.
Exemplary embodiments of coaxial RF interconnects are described in detail above. The above-described electrical interconnects facilitate electrically coupling multiple circuits to one another by use of a spring bellows to form a continuous outer conductor or shield about a coaxial transmission line that is compressible and therefore capable of accommodating variability in its length in order to maintain a good electrical connection over a range of compression. When used in combination with a spring loaded contact, the combination facilitates forming a compressible coaxial connector that maintains the electrical connection using a contact biasing force.
Additionally, the RF interconnects described herein provide an interface for flat contact pads or circuit vias and thus does not require mating sockets or pins on the printed circuit boards or RF modules. Such an embodiment may be less expensive, provide a better RF performance and operate over a wider range of compression while being less prone to workmanship errors during installation. The RF interconnects described herein have the capability of providing a high performance, low cost, compressible and repeatable blind-mate coaxial RF interconnection between two circuit elements having a variable distance therebetween. Such assemblies may be used in any application where a compressible, blind mate RF interconnect is desired. This may include, for illustrative purposes only, various aerospace applications such as array connections on a satellite.
Although the foregoing description contains many specifics, these should not be construed as limiting the scope of the present invention, but merely as providing illustrations of some of the presently preferred embodiments. Similarly, other embodiments of the invention may be devised which do not depart from the spirit or scope of the present invention. Features from different embodiments may be employed in combination. The scope of the invention is, therefore, indicated and limited only by the appended claims and their legal equivalents, rather than by the foregoing description. All additions, deletions and modifications to the invention as disclosed herein which fall within the meaning and scope of the claims are to be embraced thereby.
Although the apparatus and methods described herein are described in the context of compressible blind mate RF interconnects for use in electrically coupling two electrical components, it is understood that the apparatus and methods are not limited to such applications but may be applied by any application that supplies RF components and subassemblies, along with commercial RF electronics applications. Likewise, the system components illustrated are not limited to the specific embodiments described herein, but rather, system components can be utilized independently and separately from other components described herein.
As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural elements or steps, unless such exclusion is explicitly recited. Furthermore, references to “one embodiment” of the present invention are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.
