|Publication number||US7997537 B2|
|Application number||US 11/871,014|
|Publication date||Aug 16, 2011|
|Filing date||Oct 11, 2007|
|Priority date||Oct 11, 2006|
|Also published as||US8251316, US20080087770, US20110278400|
|Publication number||11871014, 871014, US 7997537 B2, US 7997537B2, US-B2-7997537, US7997537 B2, US7997537B2|
|Inventors||Christopher A. Rygaard, Danilo Viazzo|
|Original Assignee||Christopher A. Rygaard|
|Export Citation||BiBTeX, EndNote, RefMan|
|Patent Citations (10), Classifications (6), Legal Events (2)|
|External Links: USPTO, USPTO Assignment, Espacenet|
This application claims priority to U.S. Provisional Patent Application No. 60/851,115, filed Oct. 11, 2006, entitled “CONFORMAL AIRLOCK ASSEMBLY AND METHOD”, which is herein incorporated by reference in its entirety for all purposes.
The present invention relates in general to an airlock assembly, and more particularly, to a conformal airlock assembly particularly suitable for manned spaceflight.
Airlock assemblies have been used in space operations for human cargo space vehicles such as the U.S. Space Shuttle, as well as for space station entry and egress. Nearly all airlock assemblies are rigid wall structures that have a volume appropriate to the egress/ingress requirements of the items or humans to be accommodated. This type of rigid structure airlock is very time inefficient for ingress and egress, consumes space, expends excess energy, and a loses a significant amount of air with each cycle.
Other airlock designs include shaped airlocks which are essentially a Rigid Chamber airlocks, except the rigid chamber is shaped to match the shape of the astronaut. By shaping the rigid chamber, the volume to be evacuated and pressurized during egress and ingress is reduced, thereby reducing the drawbacks of the Rigid Chamber airlock. However, with this design, the airlock is effective with only those items of a size and shape to match the rigid chamber.
Another airlock design is a Plastic Displacement airlock system which comprises a chamber and some plastic or fluid material that floods the chamber to displace the air. This greatly reduces the air lost on each cycle. However, the amount of plastic material required to flood the chamber can result in excess weight, and it is not clear how the plastic material can be controlled to prevent it from spilling into the interior or exterior of the vehicle.
Lastly, Suit Dock airlock systems have been designed which comprise a space suit and a docking mechanism between the space suit and the space vehicle. With this design, the suit never enters the vehicle, and the astronaut must climb out of the suit and through the dock to enter the vehicle. This design allows for better dust control, as when used on a planetary surface. It also reduces cycle time, energy consumption, and air loss. However, it is strictly limited to moving personnel into and out of the space vehicle.
Accordingly, there is a need for a simple, compact airlock assembly and method for use in space operations where storage and living space is at a premium.
The present invention is directed toward a conformal airlock assembly to permit ingress and egress through a door of a support wall from a relatively high pressure environment on one side of the support wall to a relatively low pressure environment on the other side of the support wall. The airlock assembly includes a flexible, gas impermeable membrane cooperating with the support wall in an airtight manner to form an interior pocket over the door on the one side of the support wall. An airtight resealable seam is included that cooperates with the membrane to form an opening into the interior pocket from the one side of the support wall. The resealable seam is selectively operable from an open condition, permitting passage through the opening and into the interior pocket, to a closed condition, forming an airtight seal. A gas displacement system is oriented and positioned in flow communication with the interior pocket. This system is selectively operable to flow air into the interior pocket toward a non-collapsed condition for the membrane, and to flow air out of the interior pocket toward a collapsed condition for the membrane. The airlock assembly further includes an actuation system coupled to the flexible membrane which is operable to displace the flexible membrane, in the collapsed condition, away from the one side of the support wall. Such displacement of the membrane is toward a displaced condition, creating a low pressure space in the interior pocket, until the pressure within the interior pocket is sufficiently proximate to that of the relatively low pressure environment on the other side of the support wall. Hence, the door may be opened to permit ingress and egress therethrough without a large pressure differential between the pressure within the interior pocket and that on the other side of the support wall.
Accordingly, upon egress, the gas displacement system displaces air from inside the interior pocket of the membrane toward the collapsed condition. In this state, the membrane conforms around anything contained in the membrane, similar to vacuum packaging. Within the airtight interior pocket, the pressure is lowered further by operating the actuators, separating and displacing the conformed membrane, in the collapsed state, away form the support wall. This creates a low or negative pressure (i.e., a vacuum) with in the interior pocket which is adjusted to be sufficiently proximate to that of the relatively low pressure environment on the other side of the support wall. The door, accordingly, can then be safely opened.
In one specific embodiment, the airtight resealable seam is provided by any one of a resealable airtight ZIPLOCK® or ZIPPER®-style component. In addition, an overlapping metallic hook type-system and an airtight VELCRO® component may be included as well.
In another embodiment, the actuator apparatus includes one or more actuator devices. Each actuator device having one end coupled to the flexible membrane at spaced-apart locations thereof, and each having opposite ends fixedly mounted to a support structure to one of push and pull the flexible membrane. One end of each actuator device is coupled to the flexible membrane from either inside the interior pocket to push the flexible membrane away from the door, to create the lower pressure space; or outside the interior pocket to pull the flexible membrane away from the door, to create the lower pressure space.
In still another specific configuration, the gas displacement system includes a 2-way valve to selectively permit the passage of air through the displacement system. The gas displacement system cooperates with one of the flexible membrane and the support wall to permit the flow of air therethrough.
Yet another specific embodiment provides a gas permeable membrane that includes a metallic reinforced backing, particularly at the regions mounted to the ends of the actuator devices.
In another specific aspect, the present invention provides a space vehicle that incorporates a conformal airlock assembly. The space vehicle includes a hull body that defines an interior cavity, and a door to permit ingress and egress to and from the hull body. A conformal airlock assembly, in accordance with the present invention, is included for ingress and egress through the door due to the high pressure differential from the relatively high pressure environment in the interior cavity of the hull body to a relatively low pressure environment outside of the hull body. The airlock assembly includes a flexible, gas impermeable membrane cooperating with the hull body in an airtight manner to form an interior pocket over the door on the interior cavity of the hull body, and a gas displacement system in flow communication with the interior pocket. This gas displacement system is selectively operable to flow air into the interior pocket toward a non-collapsed condition for the membrane, and out of the interior pocket toward a collapsed condition for the membrane. An actuation system is included that is coupled to the flexible membrane, and operable to displace the flexible membrane, when in the collapsed condition, away from the door to a displaced condition. In this manner, a low pressure space is created within the collapsed interior pocket, forming a vacuum. The level of the vacuum is attuned to be sufficiently proximate to that of the relatively low pressure environment outside of the hull body so that the door may be opened to permit ingress and egress therethrough in a safe manner.
In still another aspect of the present invention, a method for ingress and egress is provided through a door of a support wall for vehicles, modules and structures from a relatively high pressure environment inside the support wall to a relatively low pressure environment outside the support wall The method includes providing a flexible, gas impermeable membrane that cooperates with the support wall in an airtight manner to form an interior pocket over the door on the inside of the support wall, and displacing air from within the interior pocket of the membrane from a non-collapsed condition toward a collapsed condition. In the collapsed condition, the membrane is collapsed about the door on the inside of the support wall. The method further includes displacing the flexible membrane, in the collapsed condition, away from the door on the inside of the support wall, forming a low pressure space therein. The displacing the flexible membrane is performed until the level of the low pressure within the airtight interior pocket is sufficiently proximate to that of the relatively low pressure environment on the outside of the support wall. Subsequently, the method includes opening the door to permit ingress and egress therethrough
In one specific embodiment, the method includes accessing the interior pocket of the membrane, in the non-collapsed condition, through an airtight resealable seam that cooperates with the membrane to form an opening into the interior pocket from the inside of the support wall. This is performed by selectively operating the resealable seam between an open condition, permitting passage through the opening and into the interior pocket, and a closed condition, forming an airtight seal. Just prior to accessing the interior pocket, the method include displacing air into the interior pocket of the membrane toward the non-collapsed condition until the pressure within the airtight interior pocket is sufficiently proximate to that of the relatively high pressure environment on the inside of the support wall.
In still another specific embodiment, the displacing the flexible membrane is performed by one or more actuator devices having ends coupled to the flexible membrane. In one configuration, the end of the actuator devices are coupled to the flexible membrane from an interior wall thereof, inside the interior pocket wherein the displacing the flexible membrane is performed by pushing the flexible membrane away from the door, to create the lower pressure space. In another configuration, the end of the actuator devices are coupled to the flexible membrane from an exterior surface thereof, outside the interior pocket, wherein the displacing the flexible membrane is performed by pulling the flexible membrane away from the door, to create the lower pressure space.
The assembly of the present invention has other objects and features of advantage which will be more readily apparent from the following description of the best mode of carrying out the invention and the appended claims, when taken in conjunction with the accompanying drawing, in which:
While the present invention will be described with reference to a few specific embodiments, the description is illustrative of the invention and is not to be construed as limiting the invention. Various modifications to the present invention can be made to the preferred embodiments by those skilled in the art without departing from the true spirit and scope of the invention as defined by the appended claims. It will be noted here that for a better understanding, like components are designated by like reference numerals throughout the various figures.
Referring now to
The airlock assembly 20 includes a flexible, gas impermeable membrane 25 that cooperates with the support wall 22 in an airtight manner to form an interior pocket 27 over the door 21 on the one side (hence forth, interior cavity 24) of the support wall 22. A gas displacement system, generally designated 33, is oriented and positioned in flow communication with the interior pocket 27, and is selectively operable to flow air into and out of the interior pocket 27. As will be described in greater detail below, when air is flowed into the interior pocket 27, the flexible membrane is essentially inflated and pressurized to a level substantially close to that of the pressure on the interior of the hull, as shown in the non-collapsed condition of the membrane 25 in
Once in the collapsed condition, the flexible membrane 25 which is airtight sealed and conformed about object 41, is drawn away from the object 41 or door 21 (
Accordingly, a relatively simple and cost effective airlock is provided that can be easily altered to accommodate any application involving large pressure differentials. Other advantages include rapid ingress and egress, as well as reduced air loss and power consumption compared to other airlock systems.
Referring now to
To counter the high loads and stresses acting upon the membrane by the actuation system 19, during displacement of the membrane and formation of the low pressure space 18, the metallic reinforcement backing 44 may be employed. By way of example, the metallic reinforcement backing 44 may be provided by a spider-web pattern of steel cable 28 or the like oriented around the two spaced-apart attachment points 29, 29′ (two in this example in
To provide an airtight interior pocket, the membrane 25 and the hull body 46 cooperate to form an airtight seal therebetween. Using conventional airtight mounting techniques, the seam 47 (
In accordance with the present invention, the flexible membrane 25 includes one or more resealable seams 31 that define an opening 32 into the interior pocket 27. This resealable seam 31 is movable between an opened condition (
It will be appreciated, of course, that the interior pocket 27 of the membrane should be pressurized, and at the non-collapsed condition, before the resealable seam can be moved to the opened condition. Moreover, it will be understood that the resealable seam could be positioned between the hull wall 22 and the flexible membrane 25, as opposed to two opposed portions of the membrane.
This resealable seam 31 should be capable of sufficient structural integrity to withstand the pressure differential between the low pressure side outside 26 the spacecraft 23 and the high pressure side in the spacecraft interior 24, while at the same time be capable of forming a resealable airtight seal. The seam 31 includes an airtight resealable component capable of forming an airtight seal of the opening 32. Such a resealable airtight seam may be provided by an airtight ZIPLOCK® or ZIPPER®-style component (any model numbers or anything?).
While this resealable zipper-style component is capable of providing an airtight seal, it may lack sufficient structural integrity to maintain a seal under this type of application and/or pressure differential conditions it may experience in space. Thus, to maintain structural integrity under these types of loads, the resealable seam 31 may include an overlapping metallic hook system, VELCRO® component (similar to the overlapping VELCRO® systems disposed over zippers found in many coats), for example, that works in combination with the resealable zipper-type component.
Referring now to
In one specific embodiment, the gas displacement system 33 includes a body 35 having a communication passage 36 with one end in fluid communication with the interior pocket 27 of the airlock assembly 20, and an opposite end communicating outside of the interior pocket. The displacement system 33 further includes a low pressure fan or pump device 37, or the like, operably disposed in the passage 36. This fan or pump device 37 creates or generates gas displacement to and from the interior pocket 27 of the membrane 25.
A fan with as little an output as about 0.005 PSI may be utilized, depending upon many factors such as the flexibility of the membrane, the desired capacity to collapse the membrane, etc.
Briefly, during operation of the gas displacement system to move the flexible membrane toward the collapsed condition from the non-collapsed condition (e.g., just prior to ingress or egress through the door 21, as will be described), the fan or pump device 37 operates to flow gases through the communication passage 36 in one direction (shown by arrow 42 in
While the displacement system 33 is shown and illustrated as being integrated into and through the membrane 25, it will be appreciated that the system may be integrated into and through the hull wall 22 or other part of the spacecraft 23. Moreover, the system may comprise multiple fans/pump devices as opposed to only one fan/pump device as shown.
To assure that no air leakage occurs through the displacement system passage, a valve device 38 may be positioned in flow communication with the passage 36 of the body 35 to regulate the flow of air therethrough. In an opened condition of the valve device 38 (
In accordance with the present invention, the airlock assembly 20 includes the actuation system 19 that is applied to displace the flexible membrane 25, from the collapsed condition (
In the preferred embodiment, the actuation system includes one or more actuator devices 30, 30′, each having one end coupled to the flexible membrane 25 at the corresponding attachment points 29, 29′ and opposite ends anchored to an object sufficiently stable to enable relative movement of the respective one ends. In one specific embodiment, as shown in
As best illustrated shown in the embodiments of
Briefly, referring now to
In another specific embodiment, the actuator devices may be disposed within the interior pocket 27 of the airlock assembly 20 (not shown), having an opposite end mounted to the hull wall 22 or analogous support structure of the spacecraft 23. Accordingly, rather than pulling the membrane away from the hull wall 22 from the collapsed condition to the displaced condition, as in the previous embodiment, these internal actuator devices are actuated to push the membrane away from the hull wall.
These actuators can be any type mechanism capable of displacing the membrane away from the hull wall under these loads, depending upon the number of actuators, and desired level of the negative pressure created. Such systems include pneumatic, hydraulic, cable driven mechanisms, etc., to name a few.
Referring now to
Once the resealable seam has been moved opened condition, the object 41 can be placed through the opening 32, and into the interior pocket 27 of the membrane 25. The object is preferably placed in the interior pocket 27. While the illustrations show positioning of the object near or adjacent the backside of the door 21 (
Referring now to
Once the membrane 25 is fully deflated and depressurized by the fan device 37 (in the collapsed condition), the flexible membrane 25 conforms around the object 41 to be moved (
In accordance with the present invention, the airlock assembly 20 is now in condition to depressurize the interior pocket 27. Referring now to the embodiment of
Each actuator device 30, 30′ may be operated independently and/or displace the respective portions of the membrane away from the hull wall different distances. It is the total volume of the low pressure space 18, in the displaced condition that determines level of the negative pressure or vacuum created. That is, it is preferable to displace the membrane 25 a sufficient distance away from the hull wall 22 in order to create a vacuum approximate or similar to the low pressure outside 26 of the hull wall 22. In other words, the pressure differential between the low pressure created in the low pressure space and that outside the hull body must be sufficiently low so as to enable safe and free opening of the door 21.
Once the created negative pressure is with in a safe pressure differential with that outside the hull body (e.g., vacuum or near vacuum), the door 21 can then be safely and freely opened. In effect, interior cavity 24 of the spacecraft 23 is isolated from the exterior 26 thereof (
For ingress through the airlock assembly 20 of the present invention, it is operated essentially in a manner reverse to the steps for egress. First, if the airlock assembly 20 was not just previously used for egress therefrom, with the door 21 closed, the resealable seam 31 must be moved to the closed condition, forming an airtight seal thereat. The gas displacement system 33 is then operated to flow gases out of the interior pocket 27, collapsing the membrane 25 from the non-collapsed condition to the collapsed condition. With the valve device 38 in the opened condition, the fan device 37 is operated to remove gas from the interior pocket 27, depressurizing the flexible membrane 25. As previously mentioned, the actuator devices 30, 30′ may simultaneously be operated to enable full collapse of the membrane to the collapsed condition.
The valve device 38 is subsequently moved from the opened condition to the closed condition, wherein the actuation system 19 is now ready to operate to create the proper vacuum therein. As indicated, the actuator devices 30, 30′ are actuated to displace the membrane 25 away from the hull wall 22, as shown in
Once the proper low pressure is created, substantially proximate to that outside the hull wall 22, the door 21 can be opened, as shown in
Either way, the object 41 can be moved through the door 21 and into the interior pocket 27 of the membrane, as best viewed in
Referring back to
The valve device 38 is then moved from the closed condition to the opened condition (
Subsequently, the resealable seam 31 can then be moved from the sealed closed condition to the opened condition (
In a finite volume application, such as in the interior cavity of a hull body 46 of a spacecraft, the pressure in the spacecraft itself would rise as the membrane 25 is displaced by the actuator devices 30, 30′ to create the low pressure space 18 within the interior pocket 27 of the membrane. This pressure increase, of course, collectively acts upon the exterior surface of the membrane 25, thereby increasing the forces necessary to displace the membrane toward its displaced condition. Hence, very powerful actuator devices are required to displace the membrane from the hull wall.
One solution would be to provide a constant volume, dual airlock assembly (not shown), wherein two airlock assemblies are placed in the space craft. These two airlock assemblies would be synchronized so that while one is inflating (pressurizing), the other is deflating (depressurizing). In this manner, there would be no pressure rise inside the interior body of the spacecraft as the airlock assemblies were cycled.
Moreover, if the two airlock assemblies were disposed on opposite sides of the craft in an opposed manner, the two membranes could be interconnected, via cables or the like. The dual airlock assemblies would be inherently synchronized. Much smaller capacity actuator devices could be applied since the forces acting upon one membrane would nearly cancel out the forces acting upon the other membrane.
If the two opposing airlock assemblies are sufficiently close and adjacent one another, the airlocks could employ a common membrane disposed therebetween. This would then eliminate the need for the interconnecting cables. A similar effect could be achieved with a lever mechanism between two airlocks on the same side of the craft.
While this invention has been described in terms of several preferred embodiments, there are alteration, permutations, and equivalents which fall within the scope of this invention. For example, the airlock assembly of the present invention may be utilized for ingress and egress for a clean room. This could be made from two membranes, instead of a hull wall and a membrane. In this embodiment, there would be no need for the actuators. In another application, the airlock assembly may have underwater applications, such as for ingress and egress for a submarine. In this application, “inside” and “outside” would be reversed in the figures. Moreover, the airlock assembly could also be applied to the field of environmental containment. This could be to keep contaminants inside a contaminated space, and/or retain contaminants out of an uncontaminated space. For example, the present invention may be applied for battlefield vehicles during a chemical or biological attack. It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present invention. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and equivalents as fall within the true spirit and scope of the present invention.
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|Cooperative Classification||B64G1/46, B64G1/60|
|European Classification||B64G1/46, B64G1/60|
|Oct 11, 2007||AS||Assignment|
Owner name: RYGAARD, CHRISTOPHER A., CALIFORNIA
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:VIAZZO, DANILO;REEL/FRAME:019950/0423
Effective date: 20071010
|Jan 22, 2015||FPAY||Fee payment|
Year of fee payment: 4