Patent
Antenna window cover
| العنوان: | Antenna window cover |
|---|---|
| Patent Number: | 4,916,461 |
| تاريخ النشر: | April 10, 1990 |
| Appl. No: | 07/379,683 |
| Application Filed: | July 13, 1989 |
| مستخلص: | A cover for an elongated antenna window of a nose cone of a reentry type missile includes a four directional composite material. A respective portion of a plurality of fibers are disposed in each of the four directions. The directions are oriented so that the fibers provide increased resistance to expected aerodynamic pressure-induced shear forces, especially during reentry, in the plane of the longitudinal axis of the window. The fibers comprise a refractory ceramic such as silica, boron nitride, alumina, aluminum nitride or a combination thereof having a filler material including a refractory ceramic disposed in the interstices between the fibers. |
| Inventors: | Brazel, James P. (Berwyn, PA) |
| Assignees: | General Electric Company (Philadelphia, PA) |
| Claim: | What is claimed is |
| Claim: | 1. A method for protecting the environment of a cavity, the cavity disposed internal a structure having a central longitudinal axis and an external aerodynamic surface disposed about the longitudinal axis, the external surface having a meridian, and the structure further having an aperture disposed between the external surface and the cavity, the aperture terminating at the surface in an elongated orifice and at the cavity, the aperture forming an electromagnetic flow communication path between the cavity and surroundings external to the structure, the orifice having a long axis and a shorter axis transverse the long axis, the long axis of the orifice disposed coincident with the meridian of the surface, the method comprising |
| Claim: | disposing a dielectric material over the aperture at the orifice, the material having a complementary contour to the orifice for sealingly engaging the margin of the orifice, wherein the material includes a plurality of fibers and further wherein a respective portion of the plurality of fibers are disposed in a repeatable cell substantially in a respective one of four directions, the cell including |
| Claim: | a first direction lying in a first plane, the first plane including the central longitudinal axis of the structure and the long axis of the orifice, the first direction substantially parallel to the long axis of the orifice; |
| Claim: | a second direction lying in a second plane, the second plane substantially perpendicular to the first direction, the second direction substantially parallel to the shorter axis of the orifice; |
| Claim: | a third direction lying in a third plane, the third plane spaced from and parallel to the first plane, the third direction oblique the first direction; |
| Claim: | a fourth direction lying in a fourth plane, the fourth plane spaced from and parallel to the first plane and disposed on the opposite side of the first plane from the third plane, the fourth direction oblique the first direction and opposite to the third direction; and |
| Claim: | the first direction also lying in a fifth plane, the fifth plane spaced from the fourth plane and parallel to the first plane and further disposed on the opposite side of the fourth plane from the first plane; |
| Claim: | disposing filler material including dielectric material in interstices among the plurality of fibers for supporting the plurality of fibers; and |
| Claim: | sealing engaging the margin of the orifice with filler material and fibers selected from the group consisting of fibers disposed in the first, third, and fourth directions and any combination thereof, such that elements disposed in the first, third and fourth directions also lie parallel to a plane containing the longitudinal axis and the meridian regardless of the circumferential position of the elongated orifice about the longitudinal axis of the structure. |
| Claim: | 2. The method as in claim 1, wherein the aerodynamic surface is conical. |
| Claim: | 3. The method as in claim 1, wherein the structure includes a missile nose cone and further wherein the orifice is substantially oval and has an aspect ratio of at least about 1.5 to 1. |
| Claim: | 4. The method as in claim 1, wherein the structure includes a missile nose cone and further including the step of maintaining the aperture at a predetermined attitude with respect to a predetermined passive terrestial reference when the missile is in flight. |
| Claim: | 5. The method as in claim 3, wherein the dielectric material includes a first refractory ceramic. |
| Claim: | 6. The method as in claim 5, wherein the first refractory ceramic is selected from the group consisting of silica, alumina, boron nitride, aluminum nitride and combinations thereof. |
| Claim: | 7. The method as in claim 5, wherein the filler material includes a second refractory ceramic. |
| Claim: | 8. The method as in claim 7, wherein the second refractory ceramic is selected from the group consisting of silica, alumina, boron nitride, aluminum nitride and combinations thereof. |
| Claim: | 9. The method as in claim 7, wherein the first refractory ceramic and the second refractory ceramic are the same. |
| Claim: | 10. A nose cone of a reentry-type missile comprising |
| Claim: | a structure having an aerodynamic external surface disposed about a central longitudinal axis of the structure, the surface having an elongated orifice, the orifice having a long axis and a shorter axis transverse the long axis, the long axis of the orifice disposed substantially parallel to the longitudinal axis of the structure and further disposed coincident with a meridian of the surface; |
| Claim: | aperture means terminating at the orifice, the aperture means forming an electromagnetic flow communication path between the surroundings external to the structure and cavity means disposed within the missile, the cavity means for accommodating electronic components; |
| Claim: | cover means coupled to the structure, the cover means for sealingly engaging the margin of the orifice for protecting the environment of the cavity means from the surroundings external the structure while permitting electromagnetic flow communication between the surroundings external the structure and the cavity means through the cover means, wherein the cover means includes a four directional composite dielectric material having a greater resistance to a predetermined magnitude of stress directed in the plane determined by the long axis of the orifice and the thickness direction of the cover means when coupled to the structure than to the predetermined magnitude of stress directed in the plane determined by the shorter axis of the orifice and the thickness direction of the cover means when coupled to the structure, the plane determined by the long axis disposed parallel to a plane containing the meridian and the longitudinal axis of the structure regardless of the circumferential position of the orifice about the longitudinal axis of the structure. |
| Claim: | 11. The nose cone as in claim 10, wherein the composite material includes a refractory ceramic. |
| Claim: | 12. The nose cone as in claim 11, wherein the refractory ceramic is selected from the group consisting of silica, alumina, boron nitride, aluminum nitride and combinations thereof. |
| Claim: | 13. The nose cone as in claim 10, wherein the cover means includes a plurality of fibers and further wherein a respective portion of the plurality of fibers are disposed in a repeatable cell substantially in a respective one of four directions, the cell including |
| Claim: | a first direction lying in a first plane, the first plane including the longitudinal axis of the structure and the long axis of the orifice, the first direction substantially parallel to the long axis of the orifice; |
| Claim: | a second direction lying in a second plane, the second plane substantially perpendicular to the first direction, the second direction substantially parallel to the shorter axis of the orifice. |
| Claim: | a fourth direction lying in a fourth plane, the fourth plane spaced from and parallel to the first plane and on the opposite side of the first plane from the third plane, the fourth direction oblique the first direction and opposite to the third direction; and |
| Claim: | the first direction also lying in a fifth plane, the fifth plane spaced from the fourth plane and parallel to the first plane and further disposed on the opposite side of the fourth plane from the first plane. |
| Claim: | 14. The nose cone as in claim 1, wherein the orifice is substantially oval and has an aspect ratio of at least about 1.5 to 1. |
| Claim: | 15. A cover for an antenna window of a reentry-type vehicle having a longitudinal axis and a surface disposed about the longitudinal axis of the missile, the window having a longitudinal dimension and a breadth dimension transverse the longitudinal dimension, wherein the longitudinal dimension is greater than the breadth dimension and is disposed coincident with a meridian of the surface, the cover having an outer margin complementary to the contour of the window for sealingly engaging the window and further having a longitudinal axis and a breadth axis corresponding to the longitudinal dimension and breadth dimension of the window, respectively, the cover comprising |
| Claim: | a four-directional dielectric composite material having a repeatable unit, the unit including first, second, third and fourth elongated elements respectively disposed in respective first, second, third and fourth directions lying in respective first, second, third and fourth planes, the third and fourth planes disposed parallel to and on opposite sides of the first plane, and the second plane disposed perpendicular to the first direction |
| Claim: | wherein the first direction is parallel the longitudinal axis of the cover, the third direction is oblique the first direction, the fourth direction is oblique the first direction and opposite the third direction, and the second direction is perpendicular the first plane such that when the cover is operationally disposed in the window elements disposed in the first, third and fourth planes also lie in the plane parallel to a plane including the meridian and the longitudinal axis of the vehicle regardless of the circumferential position of the window around the vehicle. |
| Claim: | 16. The cover as in claim 15, wherein the outer margin of the cover is oval and has an aspect ratio of at least about 1.5 to 1. |
| Claim: | 17. The cover as in claim 15, wherein the elongated elements include refractory ceramic material selected from the group consisting of silica, alumina, boron nitride, aluminum nitride and combinations thereof. |
| Claim: | 18. The cover as in claim 17, further including filler material selected from the group consisting of silica, alumina, boron nitride, aluminum nitride and combinations thereof disposed in interstices among the plurality of elongated elements for supporting at least in part the plurality of elongated elements. |
| Claim: | 19. The cover as in claim 18, wherein the filler material includes the same refractory ceramic material as the elongated elements. |
| Current U.S. Class: | 343/872; 428/113 |
| Current International Class: | H01Q 142; B32B 512 |
| Patent References Cited: | 4121002 October 1978 Baldwin 4400421 August 1983 Stover 4721645 January 1988 Brazel 4751135 June 1988 Fenton |
| Other References: | Improved Boron Nitride-Boron Nitride Composite Material (N. D. Potter & T. M. Place)-Dec. 10, 1979. |
| Primary Examiner: | Hille, Rolf |
| Assistant Examiner: | Johnson, Doris J. |
| Attorney, Agent or Firm: | Amgott, Allen E. Checkovich, Paul |
| رقم الانضمام: | edspgr.04916461 |
| قاعدة البيانات: | USPTO Patent Grants |
| الوصف غير متاح. |