This invention relates to the field of mechanical connectors, and in particular to a connector that is suitable for coupling large objects, such as spacecraft to launch vehicles.
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, “CLAMPING CONNECTION ASSEMBLY FOR SPACECRAFT”, issued 29 Dec. 1987 to Alois Wittmann, and 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. The clampband is conventionally tensioned by bolts, and explosive bolt cutters are used to sever the bolts to release the tension. Because of the high tension requirements, the combined weight of the belt, clamps, and ancillary required devices is substantial (as much as 45 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. The explosive frangible joint is commonly used in lieu of the aforementioned V-band for large diameter structures, typically greater than 30 inches. 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. Many launched vehicles have been lost due to a failure in the explosive separation system, and many satellites have been damaged due to explosive shock.
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, and explosive joints are not commonly used on fragile devices, such as spacecraft/satellites.
A lighter, non-explosive, and reusable coupling system is disclosed in U.S. Pat. No. 6,227,493, “REUSABLE, SEPARABLE, STRUCTURAL CONNECTOR ASSEMBLY”, and its continuation-in-part, U.S. Pat. No. 6,343,770, issued 8 May 2001 and 5 Feb. 2002, respectively, to Walter Holemans; each of which are incorporated by reference herein. This reusable coupling system employs a plurality of leaves with leaf lips that are secured within a mating surface by a band. The leaves and mating surface are designed such that the tension required on the band is significantly less than the tension required on a V-band. When the band is detensioned, springs urge the leaves away from the mating surface, thereby allowing for the separation of the connected items. The leaf lips can be configured to face toward an interior of a perimeter, and the band is contracted to hold the lips against an interior mating surface; or, the leaf lips can be configured to face toward an exterior of a perimeter, and the band is expanded to hold the lips against an exterior mating surface.
Although this coupling system overcomes most of the limitations of former systems, and particularly the limitations of explosive systems, it relies upon exerting a radial force, either outward or inward, about a substantially continuous perimeter of leaf lips. Additional means, such as spring elements, are also provided to assure that the leaf lips are disengaged from the mating surface.
It is an object of this invention to provide a non-explosive and reusable coupling system that provides for substantially bistable operation. It is a further object of this invention to provide a non-explosive and reusable coupling system that integrates both the coupling and decoupling means. It is a further object of this invention to provide a non-explosive and reusable coupling system that does not require exerting a radial force. It is a further object of this invention to provide a non-explosive and reusable coupling system that does not require a continuous perimeter of engaging elements.
These objects, and others, are achieved by a coupling system that includes latching elements on a first structure that are configured to securely engage corresponding bearings on a second structure. When engaged, or when disengaged, the system is in a stable state, requiring no active force by the controlling system to maintain the system in each state. The coupling system includes a pair of coupling elements, one of which includes a plurality of latching elements, and the other of which includes a plurality of corresponding bearings. A lateral member provides simultaneous rotation of the plurality of latching elements to engage, or disengage, the latching elements from the bearings. Preferably, each latching element is coupled to the lateral member via a pinion that provides a mechanical advantage that substantially reduces the force required on the lateral member to effect the coupling or decoupling. Also preferably, the elements are formed from extruded aluminum forms, thereby providing for a relatively inexpensive and lightweight configuration.
The invention is explained in further detail, and by way of example, with reference to the accompanying drawings wherein:
Throughout the drawings, the same reference numerals indicate similar or corresponding features or functions. The drawings are included for illustrative purposes, are not drawn to scale, and are not intended to limit the scope of the invention.
The invention is presented herein using the paradigm of a spacecraft separation system, because some of the features and benefits of this invention are particularly well suited for coupling, and decoupling, spacecraft. One of ordinary skill in the art will recognize, however, that the disclosed coupling system is not limited to spacecraft applications. Of particular note, this invention is well suited for coupling large structures or large components. In space applications, the coupling system of this invention can be used to facilitate the coupling of the components of space stations, or components of habitats that must provide sealed environments on other planets or moons. In terrestrial applications, the coupling system of this invention can facilitate the joining of pipes in difficult environments, such as the artic or open-water oil platforms; similarly, the building of habitats in these environments can be facilitated by coupling preformed structures. Other applications include the sealing of large openings, such as cargo doors on ships, trucks, trains, and planes, warehouse loading docks, watertight compartments on ships, and so on.
The coupling system 100 includes a lower structure 120 that includes a plurality of latches 130, and an upper structure 170 that includes a plurality of corresponding bearings 180. These structures 120, 170 are configured to be attached to the components 110, 160 that are to be coupled together, such as a spacecraft and launch vehicle, as illustrated in
Two latches 130 and corresponding bearings 180 are illustrated in
Each latch 130 is configured to rotate about a bearing 140, to engage (
Preferably, the bearings 140 and 180 are aligned so that when the latch 130 and bearing 180 are in the latched position, counter-clockwise rotational forces (unlatching forces) are not present on the latch 130. That is, when the latch 130 and the bearing 180 are engaged, there are preferably no shear forces on structures 170 and 120. Further, when the latch 130 and bearing 180 are engaged, the system is in an energy trough, and substantial shear forces would be required to disengage the latch 130 and bearing 180. The shape of the latch 130 and the location of the pin 155 may also be configured to avoid unlatching forces when the latch 130 is in the latched position. Additionally, the outer surface of the bearing 180 preferably includes a deformable material, such as nylon, and the hook section of the latch 130 includes a substantially non-deformable material, such as steel, and the dimensions are such that the latch 130 and bearing 180 are under tension in the latched position. In this manner, the latched position is a highly stable position, and the latch remains latched without the need to continuously provide an external force. That is, the lateral member 150 is not required to continuously apply a rotational force after the latch 130 and bearing 180 achieve this stable latched state.
As illustrated in
As can be seen in these illustrations, a preferred embodiment of this invention provides a substantially self-aligning coupling system, in that once the structures 120, 170 are brought close enough together to allow the latch 130 to engage the bearing 180, the lateral movement of the member 150 serves to vertically align the bearings 180, 140. Other methods of aligning the structures 120, 170 as the latch 130 engages the bearing 180, such as shaping of the adjoining surfaces will be evident to one of ordinary skill in the art. This self-alignment is particularly advantageous for coupling large structures, such as the aforementioned space and terrestrial based habitat structures, large pipes and doors, and so on. In a space environment, where gravity cannot be relied upon to bring components together, this self-alignment is particularly advantageous. In a terrestrial environment, where gravity often makes fine alignment difficult, this self-alignment is also particularly advantageous.
Application of a force on the lateral member in the direction 101 of
In a preferred embodiment of this invention, the structures 120, 170 are formed of extruded aluminum, and are cut-to-size for the given application. As illustrated in the cross-section views of
The particular configuration of the plurality of latches 130 illustrated in
An example alternative configuration that is particularly well suited for a high-reliability application with minimal latching/unlatching force requirements is illustrated in
Of particular note, this configuration 600 uses a pinion 610 that couples a lateral member 650 to a latch element 630. This pinion 610 provides mechanical advantage to allow latching and unlatching with reduced force on the lateral member 650. The pinion 610 is configured to rotate about a bearing 640 that is fixed to the lower structure 620, and is coupled to the latch 630 by a bearing 615 that is not attached to the structure 620. The lateral member 650 and the pinion 610 are preferably coupled via a gear-tooth arrangement, as illustrated, although other forms of coupling may be used. In a preferred embodiment, the pinion 610 also includes a tang 618 that facilitates the latching and unlatching of an adjacent latch by applying a pivoting and rotating force to the adjacent latch.
When a lateral force is applied in the direction 101 by the lateral member 650, to unlatch the latches 630, the pinion 610 rotates clockwise about the fixed bearing 640, and forces the bearing 615 to move in a clockwise direction. In conjunction with the tang 618 of an adjacent pinion that provides a pivoting point at 638, the clockwise movement of the bearing 615 causes the latch 630 to move upward and counter-clockwise. The levered downward movement of the tang 618 of the adjacent pinion also applies a force that urges the latch 630 in a counter-clockwise direction. The upward and counter-clockwise rotation of the latch 630 releases it from the bearing 180, and the upper structure 670 is free to separate from the lower structure 620, as illustrated in
The tang 618 of the pinion also serves to hold the adjacent latch 630 in the unlatched position until the lateral member 650 is moved to the right, to place the latch 630 in the latched position of
Preferably, the latch 630 comprises a lightweight and inexpensive material, such as aluminum. To assure that the latched tension against the bearing 180 does not deform the hook end of the latch 630, a less deformable material, such as steel, is used as an insert 635 in the hooked end of the latch 630. Preferably, the insert 635 is shaped to further provide stability to the latched state, for example, using the “tooth” shape illustrated in
The lower 620 and upper 670 structures of the example coupling system 600 are configured similar to the structures 120, 170 of the example coupling system 100, previously discussed. To provide for a lightweight and inexpensive embodiment, these structures 620, 670, as well as the lateral member 650, are preferably formed from extruded aluminum.
The latches 630 and pinions 610 can also be “sliced” from extruded aluminum forms, to further reduce the cost of the coupling system 610. In a preferred embodiment, the latches 630 and pinions 610 are formed to be almost as thick as the space between the walls of the structure 620, to provide maximum strength and to minimize movements. To allow both the latch 630 and the pinion 610 to be this same thickness, the latch 630 and pinion 610 are suitably milled so that one is sandwiched between the other in the region where they overlay at the bearing 615. Other techniques for interleaving mechanical elements are well known in the art, including the use of layered structures.
By turning a ball screw 830, a ball nut 840 is driven up or down, and this ball nut 840 drives a tube 850 correspondingly up or down. Link elements 860 couple the tube 850 to the lateral element 650, to effect a latching-travel of the element 650 when the tube 850 moves upward, and an unlatching-travel of the element 650 when the tube 850 moves downward. Preferably, the assembly 840-850 is located on the screw 830 such that when the link elements 860 approach their maximum extent, in line with the lateral element 650, the system 600 is driven to its latched state. The arrangement of the ball nut 840 and the larger sliding tube 850 allows the motor assembly to act as a “snap-action” device as the link assembly passes its maximum extent and the link elements 860 are “overcentered”, by about two degrees. Upon snapping into position, the lateral force thereafter provided by the motor assembly is minimal.
Two motor units 810 are illustrated for driving a gear arrangement 820 to turn the ball screw 830, to provide redundancy and/or load-sharing, although one motor unit 810 could be used, with or without a gear arrangement 820.
This motor assembly is also well suited for driving multiple coupling systems, as illustrated in
The foregoing merely illustrates the principles of the invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements which, although not explicitly described or shown herein, embody the principles of the invention and are thus within the spirit and scope of the following claims. For example, as noted above, the components 110, 160 of the example embodiments of
In interpreting these claims, it should be understood that:
This application is a Divisional application of U.S. patent application Ser. No. 11/070,343, filed 2 Mar. 2005 now abandoned, and claims the benefit of U.S. Provisional Patent Application 60/555,663, filed 23 Mar. 2004, and U.S. Provisional Patent Application 60/619,805, filed 18 Oct. 2004.
Number | Name | Date | Kind |
---|---|---|---|
259601 | Swanson | Jun 1882 | A |
865498 | Kenyon | Sep 1907 | A |
1070365 | Voight | Aug 1913 | A |
1472908 | Hart | Nov 1923 | A |
2049373 | Hampe | Jul 1936 | A |
2159150 | Heintz | May 1939 | A |
2274711 | Krause | Mar 1942 | A |
2278482 | Pishvanov | Apr 1942 | A |
2296360 | Markey | Sep 1942 | A |
2631032 | Denker et al. | Mar 1953 | A |
2708301 | Wilkirson | May 1955 | A |
2708302 | Wilkirson | May 1955 | A |
2753613 | Baker, Jr. | Jul 1956 | A |
2809557 | Johnson | Oct 1957 | A |
2822207 | Steinmetz et al. | Feb 1958 | A |
2916317 | Diday | Dec 1959 | A |
2941442 | Buschers | Jun 1960 | A |
2956477 | Barr et al. | Oct 1960 | A |
2963312 | Schenk et al. | Dec 1960 | A |
3036852 | Mullison | May 1962 | A |
3056623 | Herbert | Oct 1962 | A |
3420470 | Meyer | Jan 1969 | A |
3424403 | Hull | Jan 1969 | A |
3578368 | Dupuis | May 1971 | A |
3586360 | Perrotta | Jun 1971 | A |
3722944 | Dand | Mar 1973 | A |
3737117 | Belew | Jun 1973 | A |
3744829 | Germer | Jul 1973 | A |
3753536 | White | Aug 1973 | A |
4095829 | Van Klompenburg | Jun 1978 | A |
4135377 | Kleefeldt et al. | Jan 1979 | A |
4183480 | Jakubowski, Jr. | Jan 1980 | A |
4202576 | Hasquenoph et al. | May 1980 | A |
4273368 | Tanaka | Jun 1981 | A |
4313582 | Hasquenoph et al. | Feb 1982 | A |
4318561 | Hasquenoph et al. | Mar 1982 | A |
4364249 | Kleefeldt | Dec 1982 | A |
4381583 | von Tiesenhausen | May 1983 | A |
4540873 | Kester | Sep 1985 | A |
4685376 | Noel et al. | Aug 1987 | A |
4715565 | Wittmann | Dec 1987 | A |
4790571 | Montanari et al. | Dec 1988 | A |
4898409 | Carter | Feb 1990 | A |
4905938 | Braccio et al. | Mar 1990 | A |
4929009 | Vandersluis et al. | May 1990 | A |
4984833 | Knurr | Jan 1991 | A |
5018772 | Obermeyer et al. | May 1991 | A |
5058939 | Miilu | Oct 1991 | A |
5125601 | Monford | Jun 1992 | A |
5145130 | Purves | Sep 1992 | A |
5180198 | Nakamura et al. | Jan 1993 | A |
5197695 | Anderson et al. | Mar 1993 | A |
5385387 | Kain | Jan 1995 | A |
5390606 | Harris | Feb 1995 | A |
5735626 | Khatiblou et al. | Apr 1998 | A |
6161881 | Babka et al. | Dec 2000 | A |
6227493 | Holemans | May 2001 | B1 |
6290275 | Braam et al. | Sep 2001 | B1 |
6343770 | Holemans | Feb 2002 | B2 |
6390416 | Holemans | May 2002 | B2 |
6502868 | Laspa et al. | Jan 2003 | B1 |
6672646 | Obendiek | Jan 2004 | B2 |
6688656 | Becken | Feb 2004 | B1 |
6802543 | Wakefield | Oct 2004 | B1 |
6871451 | Harger et al. | Mar 2005 | B2 |
6981724 | Denys | Jan 2006 | B2 |
7040671 | Su et al. | May 2006 | B2 |
20020185887 | Hasselgruber et al. | Dec 2002 | A1 |
20050279890 | Holemans | Dec 2005 | A1 |
Number | Date | Country |
---|---|---|
671263 | Aug 1989 | CH |
Number | Date | Country | |
---|---|---|---|
20100090066 A1 | Apr 2010 | US |
Number | Date | Country | |
---|---|---|---|
60555663 | Mar 2004 | US | |
60619805 | Oct 2004 | US |
Number | Date | Country | |
---|---|---|---|
Parent | 11070343 | Mar 2005 | US |
Child | 12471503 | US |