Aeronautics and astronautics – Spacecraft – Spacecraft formation – orbit – or interplanetary path
Reexamination Certificate
2001-09-28
2002-05-21
Poon, Peter M. (Department: 3643)
Aeronautics and astronautics
Spacecraft
Spacecraft formation, orbit, or interplanetary path
Reexamination Certificate
active
06390416
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the field of mechanical connectors, and in particular to connector assemblies for stage separation systems, such as satellite and missile systems.
2. Description of Related Art
Transport systems, such as rockets that transport satellites into space, vessels that transport submerged sections of ocean structures such as oil platforms, and the like, require a means for securely fastening different items together for transport, and reliably and easily unfastening the items for deployment. Multi-stage rockets also require a means for fastening the stages together, and reliably unfastening the stages as each stage is spent. In other situations, such as aircraft carrier based aircraft, the items are transported or stored in a disassembled state and require a means for rapidly fastening the items for deployment, and reliably and easily unfastening the items for subsequent storage or transport.
A variety of devices have been developed to secure two items together while also allowing the items to be separated quickly and reliably. In the aerospace industry, the common connection devices include bolts and bands that can be severed. Bolts are used to fasten the two items together, and an explosive charge is typically used to sever the bolts at the proper time, thereby unfastening the two items. Depending upon the application, ancillary devices such as springs may be used to urge the two items apart when the bolts are severed. To assure a reliable separation, the number of bolts used to fasten the two items is kept to a minimum; this results in load points at the bolts far in excess of the load imposed by a distributed fastening system.
Belt structures are commonly used to provide for a distributed load. A belt structure that is commonly employed to fasten items together is a “V-band”, typified by U.S. Pat. No. 4,715,565, incorporated by reference herein. The V-band includes a tension belt for securing a plurality of retainers against camming surfaces on flange members on separable spacecraft component parts. A typical V-band embodiment consists of an upper ring attached to the payload, a lower ring attached to the launch vehicle, and a clampband that is circumferentially tensioned to the flanges of the upper and lower rings, as illustrated in FIG.
1
. The upper ring
101
and lower ring
102
each have flanges that, when joined, form a “V” shaped projection
150
A. The clampband consists of a belt
110
and a plurality of clamps
120
. Each of the clamps
120
has a recess
150
B corresponding to the shape of the projection
150
A of the upper
101
and lower
102
rings. When the belt
110
is tensioned, the recesses
150
B of the clamps
120
are compressed against the projections
150
A, thereby securing the upper
101
and lower
102
rings together.
The belt
110
is conventionally tensioned by bolts (not shown) that are in line with the belt
110
, and explosive bolt cutters are used to sever the bolts to release the tension. When the tension in the belt
110
is released, the clamps
120
are free to separate from the projection
150
A, thereby decoupling the upper
101
and lower
102
rings. The conventional V band structure also includes means, such as springs, for urging the clamps
120
apart from the projection
150
A, to provide for a reliable separation. Means are also provided to retain the belt
110
and clamps
120
after separation, to minimize the occurrence of “space junk”.
For V-bands to work properly, the tension required in the tensioning belt
110
is relatively high (about 3800 pounds for a 38 inch diameter; 6800 pounds for a 66 inch diameter). This high tension requires radial stiffeners in the rings
101
,
102
. The sudden release of this stored energy generates high shock, and imposes additional requirements on the means used to retain the fast moving belt and clamps after separation. Because of the high tension requirements, the combined weight of the belt, clamps, and ancillary required devices is substantial (as much as 25 pounds for a 38 inch diameter V-band structure). The high tension requirements of V-bands often require specialized tools and instruments to tension the band. The high tension and high release shock effects also limits the reliable life of the components, thereby limiting the amount of testing that can be applied to the components that are actually flown.
Another structure that is commonly used to provide for an easily separable connection is an explosive frangible joint, as typified by U.S. Pat. Nos. 4,685,376 and 5,390,606. An explosive detonating cord is placed within a contained space that forms the frangible joint between the two items. Separation is achieved by detonating the cord within the contained space, forcing a rapid crack propagation through the frangible joint. Although the weight of an explosive frangible joint is less than that of an equivalent sized V-band, it is still substantial (as much as 17 pounds for a 38 inch diameter joint). The destructive nature of this separation system precludes testing of the joints that are actually flown.
Each of the aforementioned separation connectors also imparts a substantial shock to the connected items upon separation, and the explosive nature of the devices used for separation introduce a risk of personal injury, particularly during pre-launch assembly and testing. Because of the shock effects, such separation connectors are not commonly used on items that are routinely disassembled for storage or transport.
BRIEF SUMMARY OF THE INVENTION
It is an object of this invention to provide a separation connector that is light weight. It is a further object of this invention to provide a separation connector that allows for repeated testing. It is a further object of this invention to provide a separation connector that allows for separation with minimal shock effects. It is a further object of this invention to provide a method for connecting components that is simple, secure, and reliable. It is a further object of this invention to provide a connector component that is stiff, strong, and easy to use.
These objects and others are achieved by a separation connector that comprises a plurality of leaves with leaf lips that are secured within a mating surface by a tensioned band in one embodiment, and a compression band in another embodiment. The leaves and mating surface are designed such that the tension or compression required on the band is significantly less than the tension required on a V-band. A shear structure is also provided that minimizes translation of the leaves with respect to mating surface. In a preferred embodiment, the tensioned band is detensioned by a thermal device that melts, decomposes, or severs the band, and the compressed band is decompressed by a contraction or removal of an expansion element. When the band is detensioned or decompressed, springs urge the leaves away from the mating surface, thereby allowing for the separation of the connected items. Preferably, the leaves are hinged, allowing for ease of coupling and decoupling to the mating surface. Multiple sections of leaf elements can be employed to form a perimeter structure corresponding to the structure of the mating surface.
REFERENCES:
patent: 2159150 (1939-05-01), Heintz
patent: 3420470 (1969-01-01), Meyer
patent: 3424403 (1969-01-01), Hull
patent: 4381583 (1983-05-01), von Tiesenhausen
patent: 4540873 (1985-09-01), Kester
patent: 4685376 (1987-08-01), Noel et al.
patent: 4715565 (1987-12-01), Wittmann
patent: 4790571 (1988-12-01), Montanari et al.
patent: 4905938 (1990-03-01), Braccio et al.
patent: 5125601 (1992-06-01), Monford, Jr.
patent: 5197695 (1993-03-01), Anderson et al.
patent: 5390606 (1995-02-01), Harris
patent: 5735626 (1998-04-01), Khatiblou et al.
Jakel Kevin
McDermott, Esq. Robert M.
Planetary Systems Corporation
Poon Peter M.
LandOfFree
Reusable, separable, structural connector assembly does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Reusable, separable, structural connector assembly, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Reusable, separable, structural connector assembly will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2910613