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FIELD OF THE INVENTION 
     The present invention relates to an unfurlable rescue ladder for emergency rescue. 
     BACKGROUND 
     An exemplary prior art unfurlable rescue ladder is sold by Guardian Fall Protection Inc. of Kent, Wash., marketed as the “rapid deployment rescue ladder.” It is used for rescuing fallen workers, such as in the construction industry. The ladder is light in weight, typically formed entirely or at least primarily of a fabric material, and is easily rolled up or folded for compact stowage in a weather resistant carrying container. The ladder is unfurled for use by another worker seeking to assist the fallen worker. If the fallen worker is not able to climb up the ladder, the worker who deployed the ladder can use it to climb down to assist the fallen worker. 
     Similar light weight, unfurlable ladders are used for mountain/rock climbing. An example is the “8-Step Ladder Aider” marketed by Metolius Mountain Products, Inc. of Bend, Oreg. The ladder aider, or simply “aider,” is typically anchored to an “ascender,” a device that is fitted securely around a rope the climber climbs. The rope has been previously positioned and anchored so as to hang down from the top of the climbing objective, and so it is called a “top rope.” The ascender is adapted to slide on the rope in one direction only, being prevented by friction from sliding in the reverse direction, and is oriented for climbing so that its sliding direction is upward. The climber wears a harness that is attached via a lanyard to the ascender. As the climber climbs the rope, the climber drags the ascender up the rope, the aider along with it. As the ascender captures the climber&#39;s progress by resisting downward sliding, the climber may step on the rungs of the aider and use it as a climbing assist. 
     A device known as a “progress capture pulley” is also sometimes used in mountain/rock climbing, and is often used in construction, for hauling equipment. A rope is passed over a sheave and a cam allows the rope to feed through the pulley in one direction but not the other. 
     SUMMARY 
     An unfurlable rescue ladder is disclosed herein. The ladder includes a hanger element, a ladder portion, a connecting element, a rope, and a progress capture element. 
     The hanger element has a connecting aperture therethrough that is either “closed” or “closeable;” the connecting element has a connecting aperture therethrough that is either “closed” or “closeable;” the progress capture element has a connecting aperture therethrough, and a separate rope-passing aperture therethrough for passing the rope through the progress capture element, the connecting and rope-passing apertures being either “closed” or “closeable.” 
     Either a plurality of rung elements are attached to each other in sequence so as to form of a chain of rung elements with a first end of the chain depending from the hanger element, or a plurality of rung elements are attached to and between rail elements in sequence with respective first ends of the rail elements depending from the hanger element. 
     The hanger element is connected to the first connecting member and the first connecting member is connected to the progress capture mechanism. More specifically, to the hanger element is connected to the first connecting member such that a portion of that portion of the hanger element that surrounds the connecting aperture through the hanger element passes through the connecting aperture through the first connecting element, and a portion of that portion of the first connecting element that surrounds the connecting aperture through the first connecting element passes through the connecting aperture through the hanger element, and the first connecting member is connected to the progress capture element such that a portion of that portion of the connecting element that surrounds the connecting aperture through the connecting element passes through the connecting aperture through the progress capture element, and a portion of that portion of the progress capture element that surrounds the connecting aperture through the progress capture element passes through the connecting aperture through the first connecting element. 
     It is to be understood that this summary is provided as a means of generally determining what follows in the drawings and detailed description and is not intended to limit the scope of the invention. Objects, features and advantages of the invention will be readily understood upon consideration of the following detailed description taken in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  is an isometric drawing of a first configuration of a ladder portion of an unfurlable rescue ladder according to the present invention. 
         FIG. 2  is an isometric drawing of a second configuration of a ladder portion of an unfurlable rescue ladder according to the present invention. 
         FIG. 3  is an isometric drawing of a third configuration of a ladder portion of an unfurlable rescue ladder according to the present invention. 
         FIG. 4  is an isometric drawing of a connecting assembly for use with the ladder portions of  FIGS. 1-3  according to the present invention. 
         FIG. 5  is an isometric drawing of a preferred alternative connecting assembly for use with the ladder portions of  FIGS. 1-3  according to the present invention. 
         FIG. 6  is an elevation view of a user of an unfurlable rescue ladder according to the present invention attached to a lanyard. 
         FIG. 7  is an elevation view of a connecting arrangement for connecting the lanyard of  FIG. 6  to the connecting assembly of  FIG. 5 . 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIGS. 1-3  show various configurations of a ladder portion  12  of an unfurlable rescue ladder  10  according to the present invention. Each of the configurations includes a hanger  14  and a plurality of substantially identical rung elements  16 . 
     The ladder  10  is provided with sufficient strength to satisfy a load requirement of 310 pounds, and the hanger and rung elements are formed primarily of a flexible material so that the ladder can be rolled up, or folded, for compact storage, and unfurled when needed. Preferably the material of which the hanger and rung elements are at least primarily formed is a lightweight and weatherproof fabric material such as nylon webbing, though they may include relatively rigid materials such as aluminum, fiberglass, or carbon fiber reinforced polymer to provide rigidity where needed, such as on the rungs where a user of the ladder would step. 
       FIG. 1  shows a first configuration  12   a  of the ladder portion  12  having a hanger  14   a  and rung elements  16   a , along with side rails  18 . Like the hanger and rung elements, the side rails  18  are formed primarily of a flexible material provided with sufficient strength to satisfy the load requirement; and preferably the material of which the side rails  18  are primarily formed is a lightweight and weatherproof fabric material such as nylon webbing, though they may include relatively rigid materials such as aluminum, fiberglass, or carbon fiber reinforced polymer to provide rigidity or heft where needed, such as at the bottom end of the side rails. 
     The rung elements  16   a  are attached to and between the rails  18  in sequence at opposite ends “E-rung” of the rung elements, with opposed ends “E-rail” of the rail elements  18  attached to the hanger  14   a . Attachment of the rails to the hanger, and the rung elements to the rails, may be by any satisfactory means. Where the hanger, side rails and rung elements are all formed of fabric material, they are preferably joined together by stitches, though other joining means could be used so long as the ladder  10  satisfies the load requirement. For example, if it would be possible to satisfy the load requirement, the elements of fabric material may be joined together by use of an adhesive. 
       FIG. 2  shows a second configuration  12   b  of the ladder portion  12  incorporating the hanger  14   a  of the first configuration  12   a  with modified rung elements  16   b  that eliminate the need for side rails. 
     The rung elements  16   b  are attached to each other in sequence so as to form of a chain of rung elements, with a rung element  16   b -top that defines the top-most rung element of the chain depending from the hanger  14   a . Attachment of the rung elements  16   b  to each other, and attachment of the rung element  16   b -top to the hanger, may be by any satisfactory means. Where the hanger and rung elements are all formed of fabric material, they are preferably joined together by stitches, though other joining means could be used so long as the ladder  10  satisfies the load requirement. For example, if it would be possible to satisfy the load requirement, the elements of fabric material may be joined together by use of an adhesive. 
       FIG. 3  shows a third configuration  12   e  of the ladder portion  12  incorporating the rung elements  16   b  of the second configuration  12   b  with the ends E-rung of the top rung element  16   b -top ( FIG. 2 ) either being joined together or eliminated to define a modified hanger  14   c . Where the rung elements are formed of fabric material, the ends of the top rung element are preferably joined together by stitches, though other joining means could be used so long as the ladder  10  satisfies the load requirement. For example, if it would be possible to satisfy the load requirement, the elements of fabric material may be joined together by use of an adhesive. 
       FIG. 4  shows a ladder connecting assembly  20  for anchoring the ladder portion  12  and providing for a novel “progress capture” function of the rescue ladder  10 . 
     For use with the ladder connecting assembly  20 , the hanger  14  preferably provides a through-aperture  15 . The aperture  15  may be provided by any satisfactory means, such as being inherently provided by the through-aperture defined by the hanger  14   c  of  FIG. 3 . Where the hanger is formed of fabric material, the aperture  15  may be formed more specifically by attaching an additional length of fabric material  21  to the hanger  14 , such as by stitches, though other joining means could be used so long as the ladder  10  satisfies the load requirement. For example, if it would be possible to satisfy the load requirement, the fabric material used for forming the aperture  15  may be joined to the hanger  14  by use of an adhesive. 
     The aperture  15  is preferably centrally located on the hanger  14 , on the bilateral ladder axis indicated in  FIG. 3  as “L 1 .” 
     The aperture  15  is “closed,” meaning for purposes herein that it is contiguously surrounded by structure such that a ring encircling any portion of the structure and passing through the aperture cannot be removed from the aperture without either manipulating or damaging the structure or manipulating or damaging the ring. At the other extreme, an aperture is “open” if the ring can be removed from the aperture without contact between the structure and the ring. Between these extremes, an aperture is “closeable” if the structure defining the aperture can be selectably manipulated to provide for repetitively opening (obtaining the “open” configuration) or closing (obtaining the “closed” configuration) the aperture as desired. 
     An example of a “closed” aperture is that defined through a ring, an example of an “open” aperture is that defined through a hook, and an example of a “closeable” aperture is that defined through a carabiner. In cases where an aperture is “closeable,” it will be understood that “the structure surrounding the aperture” refers to the structure surrounding the aperture when the aperture is closed. 
     Potentially, a ring could fall out of an “open” aperture. This is also possible, though less likely, if the structure surrounding the aperture is merely “closeable” rather than being “closed,” the latter providing a maximally secure means of attachment and is preferred if it is not necessary to allow a user to change the configuration of the aperture. 
     The ladder connecting assembly  20  includes a ladder attachment connector  22  such as the D-ring shown in  FIG. 4 . The ladder attachment connector  22  has two separate through-apertures A 1  and A 2 . Like the aperture  15 , the apertures A 1  and A 2  are preferably “closed” for maximum security of attachment. Alternatively, however, they could be merely “closeable.” 
     D-rings are specific structures that are well known in the climbing arts. They may be defined generally for purposes herein as having a bilateral axis of symmetry “AS” (see  FIG. 4 ), where the aperture A 1  defines an arc of a circle extending at least 180 degrees, more preferably at least 270 degrees, and most preferably 360 degrees, which is centered about the axis AS, and where the aperture A 2  has an area that is substantially smaller than the area of the aperture A 1  by at least 10%, and has a substantially different shape due to at least the majority of its perimeter being defined by rectilinear rather than curvilinear lines, such as the edge  29 . 
     To connect the connector  22  to the ladder portion  12 , a portion of that portion of the connector  22  that surrounds the aperture A 2  of the connector  22  is passed through the aperture  15  of the hanger  14 ; and a portion of that portion of the hanger  14  that surrounds the aperture  15  is passed through the aperture A 2 . 
     The ladder connecting assembly  20  further includes a progress capture mechanism  38 , which may be either an ascender or a progress capture pulley as known and commercially provided in the climbing arts. As is standard, the progress capture mechanism  38  has two separate through-apertures A 3  and A 4 . The apertures A 3  and A 4  are typically “closed” in commercial embodiments, but either or both of these apertures could be “closeable” instead. 
     The aperture A 3  is for passing a rope  42  through the progress capture mechanism  38 . For use with the progress capture mechanism, the term “rope” is defined to mean any rope or equivalent article of manufacture commercially provided in the climbing arts for climbing purposes. 
     Ideally, the progress capture mechanism  38  allows the rope  42  to pass freely through the aperture A 4  in one direction, and prevents passage of the rope through the aperture A 4  in the opposite direction. As a practical minimum requirement, the progress capture mechanism should allow for passing the rope in the favored direction with at least ten times less force than would be needed to overcome the resistance the progress capture mechanism provides to passing the rope in the opposite direction. 
     A connector  40  is used to connect the ladder portion  12  to the progress capture mechanism  38 . For this purpose, the connector  40  has a through-aperture A 5  which, like the apertures A 1  and A 2  of the connector  22 , may be either “closed” or “closeable.” The connector  40  may be a carabiner. 
     To connect the connector  40  to the ladder portion  12 , a portion of that portion of the hanger  14  that surrounds the aperture  15  of the ladder portion  12  is passed through the aperture A 5  of the connector  40 ; and a portion of that portion of the connector  40  that surrounds the aperture A 5  is passed through the aperture  15 . 
     Similarly, to connect the connector  40  to the progress capture mechanism  38 , a portion of that portion of the progress capture mechanism that surrounds the aperture A 4  of the progress capture mechanism is passed through the aperture A 5  of the connector  40 ; and a portion of that portion of the structure that surrounds the aperture A 5  is passed through the aperture A 4 . 
     Where the ladder portion  12  is formed of fabric material, the ladder connector  22  may be provided as shown in  FIG. 5 . In such case, it may be advantageous to likewise form the ladder connector  22  of fabric material. The ladder connector  22  in this embodiment may an extension or integral part(s) of the same fabric material used in the ladder portion  12 , or it may include one or more additional lengths of fabric material joined to the hanger  14  and/or to each other. Where the ladder connector  22  includes one or more additional lengths of fabric material, the one or more additional lengths of fabric material are preferably joined to the hanger  14  and/or to each other by stitches, though other joining means could be used so long as the ladder  10  satisfies the load requirement. For example, if it would be possible to satisfy the load requirement, the one or more additional lengths of fabric material may be joined to the hanger  14  and/or to each other by use of an adhesive. 
       FIG. 5  provides an example where the hanger  14  of the ladder portion  12  as in any of the embodiments shown in  FIGS. 1-3  may be modified to incorporate the ladder connector  22 , with stitches provided such as are indicated to form the aforementioned through-aperture A 1 . 
     Since the connector  22  is either part of or attached to the hanger  14 , there is no need for the through-aperture A 2  provided in the D-ring embodiment of the ladder connector  22  shown in  FIG. 4 . It will be readily appreciated that numerous alternative configurations of the fabric embodiment of the ladder connector  22  are possible. 
     Turning now to  FIG. 6 , a typical safety line is shown for supporting a worker  24  who has fallen from a building  26 . The worker falls only a short distance as a result of being tied to the building by a lanyard  28 . The lanyard is designed to controllably lengthen as the worker falls to absorb shock. 
     The lanyard  28  is connected at one end  28   a  to a harness  30  worn by the worker at a D-ring connector  32  via a first carabiner  34   a . The connector  32  has a through-aperture A 6  which corresponds to, and which may have the same attributes as, the aperture A 1  of the connector  22 . The other end  28   b  of the lanyard is connected to the building  26  at an anchor point  36  via a second carabiner  34   b.    
     The carabiner  34   b  has a through-aperture (not visible in  FIG. 6 ) that is “closeable,” and the anchor point  36  has a through-aperture A 10 . To connect the lanyard  28  to the anchor point  36 , a portion of that portion of the connector  34   b  that surrounds the through aperture of the connector  34   b  is passed through the aperture A 10  through the anchor point  36 ; and a portion of that portion of the anchor point  36  that surrounds the aperture A 10  is passed through the through-aperture of the connector  34   b.    
     In general for purposes herein, an anchor point need not have a through-aperture. For example, an anchor point could be a railing, or post, to which the end  28   b  is tied, or around which the end  28   b  is wrapped, using any standard means. 
     After a worker has fallen from the building  10  as shown in  FIG. 6 , another person in the building (not shown) may deploy the ladder  10 , by connecting it to the building and unfurling it so that it can be accessed by the fallen worker. The connection to the building may be made through the connector  22  by use of an additional connector  46  that will be discussed immediately below in connection with  FIG. 7 . 
     However, before the worker fell he/she made the connection shown in  FIG. 6  between the end  28   a  of the lanyard and the connector  32  by installing the first carabiner  34   a  himself/herself, typically with the harness  30  already donned. Now with reference to  FIG. 7  showing the ladder unfurled and provided to the fallen worker, the worker is likewise able to connect to the rope  42  at the same attachment connector  32  by use of a “closeable” connector  44  connected to a looped end  42   a  of the rope. This allows for the person who deployed the ladder, or a person who is otherwise available to provide assistance, to use the rope  42  and progress capture mechanism  38  to capture the worker&#39;s progress as he or she climbs the ladder, by pulling on an end  42   b  of the rope such as where indicated and in the direction indicated by the arrow at “P,” to take up the slack in the rope as the worker ascends. 
     The looped end  42   a  has a through-aperture A, ( FIG. 4 ) that is “closed,” but the end  42   a  could be fitted with additional hardware that provides an aperture that is “closeable.” The connector  44  shown in  FIG. 7  has a through-aperture A 8  that cannot be seen in the Figure but is just like the aperture A 5  of the connector  40  (see  FIG. 4 ), which is in this case preferably “closeable” so the worker is able to open the aperture to make the connection to the rope  42  and close the aperture thereafter to ensure a safe connection. 
     To connect the connector  32  to the rope  42 , a portion of that portion of the end  42   a  of the rope  42  that surrounds the aperture A 7  ( FIG. 4 ) of the end  42   a  is passed through the aperture A 8  of the connector  44 ; and a portion of that portion of the connector  44  that surrounds the aperture A 8  is passed through the aperture A 8 . 
     To connect the ladder  10  to the building, the connector  22  may be connected to the anchor point  36 , or to some other attachment point in the building, by use of an additional connector  46 . The connector  46  has a through-aperture A 9  which is like the aperture A 8  of the connector  44 , very preferably being “closeable” so the person deploying the ladder is able to open the aperture to make the connection to the rope anchor point and close the aperture thereafter to ensure a safe connection. 
     To connect the ladder to the connector  46 , a portion of that portion of the connector  22  that surrounds the aperture A 1  of the connector  22  is passed through the aperture A 9  through the connector  46 ; and a portion of that portion of the connector  46  that surrounds the aperture A 9  is passed through the aperture A 1 . 
     To connect the connector  46  to the anchor point  36 , a portion of that portion of the connector  46  that surrounds the aperture A 9  of the connector  46  is passed through the aperture A 10  through the anchor point  36 ; and a portion of that portion of the anchor point  36  that surrounds the aperture A 10  is passed through the aperture A 9 . 
     It should be understood that it is not necessary for the ladder  10  to be connected to the same anchor point as the lanyard  28  that supports the person who has fallen. 
     Preferably the progress capture mechanism  38  is closely coupled to the mid-point of the hanger  14  of the ladder, so that an angle φ defined between the rope and the vertical at elevations beneath the progress capture mechanism is minimized, so that the linear translation of the end  42   a  of the rope  42  as the worker climbs the ladder is primarily in the vertical direction, along the ladder axis L 1  ( FIG. 3 ). Preferably no more than 20% of this translation is in a direction perpendicular to the vertical. 
     Preferably, the progress capture mechanism  38  is more specifically a progress capture pulley, so that the angle θ defined between the rope and the horizontal at elevations above the progress capture mechanism  38  obtained as the assisting person pulls on the rope can be significantly less than 90 degrees, e.g., between zero and 45 degrees. 
     It is to be understood that, while a specific unfurlable rescue ladder has been shown and described as preferred, other configurations could be utilized, in addition to those already mentioned, without departing from the principles of the invention. 
     The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such terms and expressions to exclude equivalents of the features shown and described or portions thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.

Summary:
An unfurlable rescue ladder. The ladder includes a progress capture element allowing someone who deploys the ladder for rescuing a person who has fallen to also assist the person to climb the ladder.