Patent Application
20120061520
The present invention relates in general to a device that provides for the attenuation of shock, and in particular, to a frangible joint having shock attenuation features formed integrally therein.
Frangible joints of various design configurations are common, for example, those comprising a hollow form extrusion. Also, various devices for shock attenuation are also known, for example, those that include a cylindrical flexible structure having one or more viscoelastic members secured to an outer surface of the cylindrical structure. In this known arrangement, the cylindrical structure has machined features to tune stiffness and shock transmissibility therethrough. The cylindrical structure may be used, for example, as a shock isolation mount between a spacecraft and a launch vehicle.
However, this arrangement suffers from the drawback that additional hardware components beyond the cylindrical structure (i.e., the viscoelastic members along with corresponding outer rigid constraining members secured to the outer surface of each viscoelastic member) are required to achieve the desired amount of shock attenuation between the launch vehicle and the spacecraft.
What is needed is a frangible joint that includes shock attenuation features formed integrally therein, thereby eliminating the need for additional components to achieve the desired amount of shock attenuation.
According to an embodiment of the invention, a frangible joint structure includes shock attenuation features formed as an integral part of the joint structure. Shock attenuation is achieved through use of, for example, slots or grooves that are machined directly, or otherwise formed integrally, into the frangible joint structure. Adequate shock attenuation is achieved solely by the features machined or otherwise formed in the frangible joint together with the typical assembly of the frangible joint into various structures (e.g., as a payload separator for rockets, missiles, satellites, etc.), without the need for additional hardware components and thus without the need for assembly of the frangible joint shock attenuation device.
The various embodiments of the present invention can be understood with reference to the following drawings. The components are not necessarily to scale. Also, in the drawings, like reference numerals designate corresponding parts throughout the several views.
The present invention is more particularly described in the following description and examples that are intended to be illustrative only since numerous modifications and variations therein will be apparent to those skilled in the art. As used in the specification and in the claims, the singular form “a,” “an,” and “the” may include plural referents unless the context clearly dictates otherwise. Also, as used in the specification and in the claims, the term “comprising” may include the embodiments “consisting of” and “consisting essentially of” Furthermore, all ranges disclosed herein are inclusive of the endpoints and are independently combinable.
As used herein, approximating language may be applied to modify any quantitative representation that may vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by a term or terms, such as “about” and “substantially,” may not to be limited to the precise value specified, in some cases. In at least some instances, the approximating language may correspond to the precision of an instrument for measuring the value.
In an embodiment of the invention, a frangible joint structure includes shock attenuation features formed as an integral part of the joint structure. Shock attenuation is achieved through use of, for example, slots or grooves that are machined directly, or otherwise formed integrally, into the frangible joint structure. Adequate shock attenuation is achieved solely by the features machined or otherwise formed in the frangible joint together with the typical assembly of the frangible joint into various structures (e.g., as a payload separator for rockets, missiles, satellites, etc.), without the need for additional hardware components and thus without the need for assembly of the frangible joint shock attenuation device.
The foregoing and other features of various disclosed embodiments of the invention will be more readily apparent from the following detailed description and drawings of the illustrative embodiments of the invention wherein like reference numbers refer to similar elements.
Referring to
Regarding the geometry of the slots 110, straight, angled and curved slots will have different effects on the amount of shock attenuation achieved by the frangible joint 100 and on the joint load capacity (longitudinal, shear and bending). Thus, referring to
The design of the slots or grooves that comprise the shock attenuation features of the invention can be applied to any of the present frangible joint styles (e.g., hollow form extrusion, tongue-in-groove, etc.). The shock attenuation features may be machined directly into frangible joint or formed in some other manner, depending in part upon the material that comprises the frangible joint. An advantage of the frangible joint of the various embodiments of the invention is that no additional components are required—thus, no assembly steps are required.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to make and use the invention. 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. All citations referred herein are expressly incorporated herein by reference.
This application claims the benefit of U.S. Provisional Application Ser. No. 61/082,689, entitled “Low Shock Frangible Joint”, filed Jul. 22, 2008, which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61082689 | Jul 2008 | US |
