Aeronautics and astronautics – Spacecraft – Spacecraft formation – orbit – or interplanetary path
Reexamination Certificate
1999-03-09
2001-10-09
Jordan, Charles T. (Department: 3644)
Aeronautics and astronautics
Spacecraft
Spacecraft formation, orbit, or interplanetary path
C403S403000
Reexamination Certificate
active
06299106
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to a method of installing thermal insulation, and more particularly, to a method and device for quickly fastening and unfastening a thermal blanket to the skin of a spacecraft.
2. Background Information
Reusable space launch vehicles, such as the space shuttle, are exposed to extreme cold and extreme heat. For example, in contrast to the subzero temperatures encountered in space, a space launch vehicle may be exposed during reentry to hull temperatures exceeding 1,800° F. Some form of thermal insulation is required to protect the space launch vehicle from these extremes in temperature. Currently, the space vehicles use ceramic tiles as protection. However, it has been suggested that as an alternative, flexible quilted ceramic blankets
20
, as shown in
FIG. 1
, could be used to cover the exteriors of such space vehicles for protection.
The proposed flexible blankets
20
, shown in
FIG. 1
, are constructed of a fiber batting
22
. The batting
22
is surrounded by a cover material
24
, and quilted with ceramic thread
26
to form the blanket
20
.
The blankets
20
are mounted onto a hull exterior
29
of the space vehicle
28
with a silicon rubber adhesive
30
, as shown in FIG.
2
. Unfortunately, the blankets
20
when adhered to a structure using the silicon rubber adhesive
30
, often do not withstand high acoustic loads to which the space vehicle
28
are subjected during reentry. Acoustical loads of this magnitude often cause the quilting threads to break, and the batting to separate and puff up. This reduces the performance of the insulating blanket to unacceptable levels. Another disadvantage of mounting the blankets
20
with the silicon adhesive
30
is that the adhesive
30
becomes brittle over areas having very low temperatures, such as over cryotanks.
Yet another disadvantage of mounting the blankets
20
onto the space vehicle
28
using the silicon rubber adhesive
30
, as shown in
FIG. 2
, is that the blankets
20
must often be removed and replaced for inspection, repair, or to obtain access to various hatches. The current process for removing the blankets
20
requires the blankets
20
to be literally scraped off the hull
29
of the launch vehicle
28
. The removal process is both time consuming and expensive. Since turnaround time for reusable launch vehicles is increasingly critical to their success, the extensive time required for the removal and replacement of insulation blankets mounted with adhesive is unacceptable.
Attempts to replace the silicon rubber adhesive
30
with a mechanical device have so far failed because the mechanical devices have failed to prevent the blankets
20
from sagging in the areas where the blankets were not mechanically fastened to the vehicle hull
29
. When attempts to mechanically fasten the blankets
20
to the hull
29
were attempted, the mechanical fastener was exposed on the exterior of the blanket to enable the use of tooling to remove and install the blanket
20
onto the hull
29
of the vehicle
28
. Unfortunately, testing showed that these exposed areas act as heat sinks, which draw the heat of reentry into the hull causing hull failure. Further, any attempts to attach the mechanical devices to the hull
29
would be difficult to remove once drilled or welded to the exterior of the hull
29
.
Accordingly, there is a need in the art for a means of quickly installing and removing the flexible blankets
20
from the hull
29
of the space vehicle
28
. Further, any means for holding the blankets in position must prevent sagging, and be reliable even when exposed to intense vibration and heat, typically encountered during a space vehicle's reentry into the earth's atmosphere.
SUMMARY OF THE INVENTION
In one aspect, the present invention relates to a thermally insulated spacecraft including a skin external to the spacecraft, a plurality of studs affixed to the skin, and an insulating blanket for positioning over at least a portion of the skin. The blanket includes a frame member forming a shape having a plurality of corners, ceramic fiber batting supported by the frame, ceramic fabric cover sewn over the ceramic fiber batting, a mounting flange positioned in each of the plurality of corners of the frame members, and a snap fastener seated in each mounting flange for coupling the insulating blanket to the plurality of studs. The snap fastener has a base intersecting the mounting flange. The base includes a barrel having a length perpendicular to the frame member wherein the barrel has at least two orifices in a plane orthogonal to a radial axis of the barrel. The fastener also has a plurality of balls, each sized to fit a respective one of the at least two orifices, a fastener for holding a first end of the base onto the mounting flange, a cap positioned adjacent a second end of the base, a spring positioned between the cap and the second end opposite of the first end of the base, and a collar press fit into a lower portion of the cap to limit the movement of the cap from the base.
In another aspect, the present invention relates to a thermal insulating blanket for insulating a surface from extreme external temperatures. The blanket includes ceramic fiber batting that insulates the surface from the external temperatures, a frame for supporting the ceramic fiber batting and preventing the ceramic fiber batting from sagging, and a ceramic fabric cover enclosing the ceramic fiber batting and the frame. The ceramic fabric cover defines a first side of the blanket facing externally, and a second side opposite the first side and facing the surface. The blanket also includes a low profile fastener for coupling the blanket to the surface, the fastener coupled and decoupled from the surface by applying pressure to the first side of the blanket proximate the fastener.
In yet another aspect, the present invention relates to a method for engaging and disengaging a rectangular thermal blanket, which is filled with insulating material and has a plurality of low profile snap fasteners, each covered by the insulating material and coupled to a respective corner of the blanket, with a surface having a plurality of studs. The method includes the steps of aligning each of the studs with a corresponding one of the snap fasteners, applying pressure over each corner of the thermal blanket until the thermal blanket is secured to the surface, and applying pressure over each corner of the thermal blanket proximate to the respective snap fastener until it disengages from a respective one of the studs and removing the thermal blanket from the surface.
REFERENCES:
patent: 2402925 (1946-06-01), Spooner
patent: 2901804 (1959-09-01), Williams
patent: 3117484 (1964-01-01), Myers
patent: 3233496 (1966-02-01), DePew et al.
patent: 3827110 (1974-08-01), Dzus, Sr. et al.
patent: 3896698 (1975-07-01), Aylott
patent: 4453449 (1984-06-01), Hollmann
patent: 4456208 (1984-06-01), MacConochie et al.
patent: 4906123 (1990-03-01), Weskamp et al.
patent: 4919366 (1990-04-01), Cormier
patent: 5154373 (1992-10-01), Scott
patent: 5178922 (1993-01-01), Ferrier et al.
patent: 5207544 (1993-05-01), Yamamoto et al.
patent: 5452979 (1995-09-01), Cosenza
patent: 5489074 (1996-02-01), Arnold et al.
patent: 5494323 (1996-02-01), Huang
patent: 5511747 (1996-04-01), Parrot et al.
patent: 5642960 (1997-07-01), Salice
patent: 5759659 (1998-06-01), Sanocki et al.
patent: 5797643 (1998-08-01), Demedash
Dinh Tien
Jordan Charles T.
Nelson Lawrence W.
The Boeing Company
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