Patent Application
20070286345
There are herein provided methods and apparatus useful for imaging systems such as, for example, but not limited to a digital x-ray system. The apparatus and methods are illustrated with reference to the figures wherein similar numbers indicate the same elements in all figures. Such figures are intended to be illustrative rather than limiting and are included herewith to facilitate explanation of an exemplary embodiment of the apparatus and methods of the invention.
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 said 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.
In one embodiment, the panel support 14 is layered with a thin foam sheet 12 that absorbs out-of-plane shocks, distributes point loads, increases lateral friction, and provides a uniform gap between the panel 20 and the support 14 in areas where foam is absent (voids). Additionally, the compliant (resilient) nature of the resilient sheet 12 reduces bending stresses in the panel 20 and the panel support 14 as the assembly 10 is assembled. The support foam is configured to have less surface area than the panel by selectively cutting small areas from it, thereby creating voids for the potting material to fill. Alternatively, the foam sheet can be manufactured with voids. Also, in the embodiment without discrete voids, the sheet can be shaped the same as the support and panel but with smaller dimensions and then the voids are just the places where there is no foam between the panel and the support. Additionally, it is meant herein that the term “area” refers to just the area of the sheet that is over the panel support and under the area of the panel. For example, the total area of the sheet may be greater than the total area of the panel support but positioned such that at least one void is created between the panel support 14 and the panel 20. And thus, the “area” (as used herein) of the sheet in that example is still less than the area of the panel and the panel support. If the small areas are arranged near the perimeter of the foam, they are later accessible from the edge of the stack by an Exacto knife or other thin cutting device for easy removal. The voids are filled with a flexible, wet adhesive such as an RTV (room temperature vulcanizing) silicon manufactured by the General Electric Company. The panel is laid on the support foam, compressing the uncured adhesive to the thickness of the support foam. The stack-up is clamped until the adhesive has cured. The thickness of the support foam allows the thin knife to cut the RTV and remove the panel from the support. The flexibility of the potting material and the underlying support foam inhibit shock transmission from the panel support. The caulk-like properties of a wet adhesive like an RTV aids positioning during assembly as compared to double-sided tapes.
One advantage is the flexible and re-workable nature of the herein described potting method. The thin, uniform thickness layer of foam and the flexible potting material provide the height necessary to slice the bond. In one embodiment, the resilient sheet (the foam) is about 1/32 in or about 0.8 mm thick. In another embodiment, the sheet's thickness is about 1/16 in or 1.58 mm. The foam provides an inherent cushion. Typically, the area of sheet compared to the total area of the voids is quite large. For example, in one embodiment the area of the sheet is 90% (or greater) of the area of the panel.
Technical effects of the flexible potting method include the reduction of shock transmissions from the panel support to the panel, the allowance of the panel and/or flexes to be reworked or repaired thus sparing the cost of panel, (flexes are approximately 1/20th the cost of a panel), and the embodiment with the perimeter bond allows other thin sheet-like materials to be inserted between the panel and support in the middle area. Also, the herein described methods and apparatus allow for the re-positioning during assembly compared to double-sided tapes that do not allow for re-positioning. The foam spacer has an additional benefit of thermally isolating the temperature-sensitive panel from the panel support and warm electronics.
It is contemplated that the benefits of the invention accrue to both medical imaging systems and non-medical imaging systems such as those systems typically employed in an industrial setting or a transportation setting, such as, for example, but not limited to, a baggage scanning digital x-ray imaging system for an airport or other transportation center.
Exemplary embodiments are described above in detail. The assemblies and methods are not limited to the specific embodiments described herein, but rather, components of each assembly and/or method may be utilized independently and separately from other components described herein.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.
