Patent Publication Number: US-8534420-B1

Title: Apparatus and method for safely lowering user from structure

Description:
FIELD 
     This disclosure relates generally to emergency and safety devices, and in particular, to an apparatus and method for safely lowering a user from a structure, such as a building, house, bridge, equipment or other type of structures. 
     BACKGROUND 
     Residential and commercial buildings are often equipped with many safety features in order to deal with emergency situations. For instance, buildings often include smoke detectors and alarms adapted to alert people of an on-going fire to allow them to take safety measures, such as exiting a building in a safe manner. Additionally, many buildings include a network of fire extinguishers and fire-protected stairwells to protect those from harm due to fire and smoke. Often, these measures of alerting and protecting building dwellers are sufficient. 
     On occasion, a building may be damaged in such a way as to prevent the safe egress from the building. For example, the stairwell or exit corridor may be consumed with smoke or fire. Similarly, the exit path may be blocked due to earthquake damage. For people in a single story building or on the first or perhaps the second floor of a building, this may not be a problem because people may, to some degree, safely exit the structure through a window or door. 
     In situations that involve a multi-level or high-rise building, this situation of a blocked egress in the building may present a difficult or dire problem for the habitants. If, for example, some of those people are present at the lower seventh floors of a building, a fire truck ladder may be used to reach them, and bring them down in a safe manner. This is assuming that those people are able to wait out the emergency until a fire truck arrives. This may not always be the case. 
     In cases where building dwellers are above the seventh floor, other means, perhaps a rescue helicopter, may be needed to safely remove those inside the building. This may not always be possible, as in the case of the 9/11 New York City&#39;s twin tower disaster. Not only are the building dwellers susceptible to this kind of adverse situation, but fire fighters as well may get trapped in a multi-level building with no easy course-of-action to safely exit the structure. Thus, there is a need for an apparatus to facilitate a safe egress from a multi-level or high-rise building or structure. 
     SUMMARY 
     An aspect of the disclosure relates to an apparatus for safely lowering a user from a structure. The apparatus comprises a ring structure configured to coaxially surround a pole structure including a spiraling inclined surface, wherein the ring structure comprises a circular track. The apparatus further comprises a brake mechanism including a first portion configured to travel along the spiraling inclined surface and a second portion configured to travel along the circular track when the apparatus is descending. Additionally, the apparatus comprises a user support assembly for supporting a user when the apparatus is descending, wherein the user support assembly is securely coupled to the ring structure. The acceleration and braking forces are direct function of the weight of the mass being lowered (the apparatus including the user), the inclination angle of the spiraling inclined surface, and the coefficient of friction of the brake pad sliding on the spiraling inclined surface. 
     In another aspect of the disclosure, the first portion of the brake mechanism comprises a brake pad configured to frictionally slide along the spiraling inclined surface of the pole structure when the apparatus is descending. The brake mechanism may further comprises a roller bearing (one or more rollers) having a rotational axis substantially perpendicular to the plane of the inclined surface. The roller bearing is situated between the brake pad and a raised outer edge of the spiraling inclined surface. The roller bearing prevents the brake pad from slipping off the spiraling inclined surface due to centrifugal force. Additionally, the brake mechanism further comprises a pivot coupling between the brake pad and a rod coupling the first portion to the second portion. The pivot coupling allows the brake pad to pivot to accommodate different inclinations for the spiraling inclined surface. As an example, the inclination of the spiraling inclined surface may vary to control the rate of descent, such as to slow the rate of descent near ground or the landing zone. 
     In another aspect of the disclosure, the user support assembly comprises a seat or a net to support a user while the apparatus is descending. In another aspect, the user support assembly comprises a fixed member securely coupled to the ring structure, and a vertically-adjustable member coupled to the fixed member by way of a vertically-adjustable interface. In yet another aspect, the vertically-adjustable interface comprises a ratchet interface. In still another aspect, the user support assembly comprises one or more cranks configured to allow a user to adjust the ratchet interface to change a vertical position of the vertically-adjustable member with respect to the fixed member. In an additional aspect, the seat or net may be securely coupled to the vertically-adjustable member. 
     In still another aspect of the disclosure, the apparatus comprises a torque limiting mechanism configured to prevent or reduce axial rotation of the ring structure when the apparatus is descending. In yet another aspect, the torque limiting mechanism comprises an arm extending radially away from the ring structure, and a roller rotationally attached to an end portion of the arm, wherein the roller is configured roll vertically along a vertical fixed member of the structure when the apparatus is descending. 
     In yet another aspect of the disclosure, the ring structure comprises a hinge configured to pivotally separate a first portion from a second portion of the ring structure at a first angular location of the ring structure, and a lock configured to selectively lock the first and second portions together at a second angular location of the ring structure. In another aspect, the lock is configured to engage with an unlocking mechanism while the ring structure is descending near ground or a landing zone, wherein the unlocking mechanism is configured to unlock the lock to facilitate separation of the first portion from the second portion at the second angular location of the ring structure. This allows the ring structure to be removed from the pole structure. 
     Other aspects, advantages and novel features of the present disclosure will become apparent from the following detailed description of the disclosure when considered in conjunction with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A-1B  illustrate top and side views of an exemplary apparatus for safely lowering a user from a structure in accordance with an aspect of the disclosure. 
         FIGS. 2A-2B  illustrate top and side views of another exemplary apparatus for safely lowering a user from a structure in accordance with another aspect of the disclosure. 
         FIGS. 3A-3B  illustrate top and side views of still another exemplary apparatus for safely lowering a user from a structure in accordance with another aspect of the disclosure. 
     
    
    
     DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS 
       FIGS. 1A-1B  illustrate top and side views of an exemplary apparatus  100  for safely lowering a user from a structure in accordance with an aspect of the disclosure. In summary, the apparatus  100  includes a rate-of-descent controlling device in the form of a ring structure or member configured to coaxially surround a pole structure with a spiraling inclined surface. The apparatus  100  also includes a brake mechanism configured to travel along the spiraling inclined surface and along a circular track incorporated into the ring structure. The apparatus  100  further includes a torque limiting mechanism to prevent rotation of the apparatus while it is descending. Additionally, the apparatus  100  further includes a user support assembly coupled to the ring structure for supporting a user during descent. 
     More specifically, with reference to  FIG. 1 , the apparatus  100  comprises a ring-shaped structure or member  110  that includes a circular track  112  incorporated therein. The ring structure  110  is configured to coaxially surround a pole structure  180  that includes a spiraling inclined surface  182 . The pole structure  180  may be positioned proximate a structure  190 , such as a building or housing, to allow a user to escape the structure using the apparatus  100 . 
     The apparatus  100  further comprises a brake mechanism  114  that includes an upper portion  118 , such as a ball-shaped structure, configured to travel or ride along the circular track  112  of the ring structure  110  as the apparatus  100  descends. An appropriate bearing may be provided to facilitate the movement of the upper portion  118  of the brake mechanism  114  along the track  112  of the ring structure  110 . The brake mechanism  114  further comprises a brake pad  116  configured to frictionally slide along the spiraling inclined surface  182  of the pole structure  180  as the apparatus descends. The brake mechanism  114  further comprises a rod  120  to mechanically connect the upper portion  118  to the brake pad  116 . The inclination of the spiraling inclined surface  182  and the friction encountered by the brake pad  116  as it slides along the surface  182  may be configured to provide a desired rate of descent for the apparatus. 
     The brake mechanism  114  further comprises a roller bearing  117  positioned between the brake pad and a raised outer edge  184  of the spiraling inclined surface  182 . The roller bearing  117  may include one or more rollers having a rotational axis substantially perpendicular to the plane of the spiraling inclined surface  182  at the present location of the brake mechanism  114 . The one or more rollers are configured to roll along the raised outer edge  184  of the spiraling inclined surface  182 . The roller bearing  117  assists in preventing the brake pad  116  from slipping off the spiraling inclined surface  182  due to centrifugal force. 
     Additionally, the brake mechanism  114  comprises a pivot coupling  119  between the rod  120  and the brake pad  116 . The pivot coupling  119  allows the brake pad  116  to pivot to maintain it substantially flat on the spiraling inclined surface  182  as the inclination of the surface  182  is changed. The inclination of the spiraling inclined surface  182  may change along the height of the pole structure  180  to control the rate of descent of the apparatus  100 . For example, at a threshold height above ground or the landing zone, the inclination may be greater to cause the apparatus to descend relatively fast. Below the threshold height, the inclination may be less in order to slow down the descent of the apparatus near ground or the landing zone. 
     The apparatus  100  further comprises a torque limiting mechanism  130  configured to prevent rotation of the ring structure  110 , or for that matter, the apparatus as it descends. That is, as the apparatus  100  descends, the brake mechanism  114  as it travels along the circular track  112  in a clockwise direction as seen from the top view of  FIG. 1A , exerts a torque on the ring structure  110  which would otherwise cause it to rotate in the same clockwise direction. To prevent this rotation, the torque limiting mechanism  130  comprises an arm  132  that extends outward from the ring structure  110  and substantially perpendicular towards a wall or vertical member of the structure  190 . The torque limiting mechanism  130  further includes a roller  134  at an end portion of the arm  132 . The roller  134  is configured to rotate about a substantially horizontal axis, and is configured to roll along the wall or vertical member of the structure  190  as the apparatus descends. The abutment of the roller  134  against the wall or vertical member of the structure  190  counters the torque created by the brake mechanism  114  to prevent the apparatus  100  from rotating as it descends. 
     The apparatus  100  further comprises a user support assembly  140  for securely supporting a user, while the user and the apparatus descend to ground or a safe landing zone. The user support assembly  140  comprises a fixed member  142  that is securely coupled or attached to the ring structure  110  by one or more braces  144 . The user support assembly  140  further comprises a vertically-adjustable member  146  coupled to the fixed member  142  by way of a ratchet interface  150 . The apparatus  100  further comprises one or more cranks  152  to allow a user to adjust the vertical position of the vertically-adjustable member  146  with respect to the fixed member  142 . The user support assembly  140  further comprises a seat  160  securely attached to the vertically-adjustable member  146 . In this configuration, the user adjusts the vertical position of the seat  160  by way of the one or more cranks  152  and the ratchet interface  150 , so when the apparatus  100  descends to its lowest position, the seat  160  lies above ground or the landing zone at an appropriate distance based on the height of the user. The user support assembly  140  may further comprise a seat belt  162  to securely maintain the user on the seat  160  while the apparatus  100  descends. 
       FIGS. 2A-2B  illustrate top and side views of another exemplary apparatus  200  for safely lowering a user from the structure  190  in accordance with another aspect of the disclosure. The apparatus  200  is similar to the previous embodiment  100 , and includes many of the same elements as indicated by the same reference numbers. The apparatus  200  differs from apparatus  100  in that it comprises a user support assembly  240  that includes a net  260  instead of a seat  160 . The net  260  is securely attached to the vertically-adjustable member  146  of the user support assembly  240 . It shall be understood that other types of user support structures may be used, such as a harness or a step. 
       FIGS. 3A-3B  illustrate top and side views of still another exemplary apparatus  300  for safely lowering a user from the structure  190  in accordance with another aspect of the disclosure. The apparatus  300  is similar to the previous embodiments  100  and  200 , and includes many of the same elements as indicated by the same reference numbers. The apparatus  300  differs from apparatuses  100  and  200  in that it comprises a ring structure  310  that opens to allow the apparatus  300  to be removed from the pole structure  180  when the user reaches ground or the landing zone. 
     In particular, the ring structure  310  comprises a hinge  321  located along an outer surface of the ring structure at a first angular location. The hinge  321  pivots about a substantially vertical axis, and allows the ring structure to pivotally separate at the first angular location. The ring structure  310  also comprises a lock  322  located along the outer surface of the ring structure at a second angular location. The angular spacing between the first and second angular locations may be substantially 180 degrees. However, it shall be understood that other angular spacing between the hinge  321  and the lock  322  may be provided. The lock  322  securely holds two halves or sides of the ring structure  310  at the second angular location. 
     The lock  322 , in turn, comprises an upper bore  324   a  securely attached to one of the halves or sides of the ring structure  310 ; for example, securely attached to the lower-right half or side of the ring structure  310  as seen from the top view depicted in  FIG. 3A . The lock  322  further comprises a lower bore  324   b  securely attached to the other one of the halves or sides of the ring structure  310 ; for example, securely attached to the upper-left half or side of the ring structure  310  as seen from the top view depicted in  FIG. 3A . The lock  322  further comprises a pin that includes a lower portion  326  situated axially within the upper and lower bores  324   a  and  324   b  when the ring structure  310  is closed and locked, and an upper portion  328  configured as a lip extending horizontally and radially away from the ring structure  310 . The upper and lower bores  324   a  and  324   b  and the lower portion  326  of the pin may include substantially the same non-circular cross section in order to fix the orientation of the lip  328  of the pin. 
     Near ground level or the landing zone  195 , a stop  184  is provided to prevent the ring structure  310  from descending beyond the stop. The stop  184  may be securely attached to the pole structure  180  as shown, may be securely attached to the structure  190 , or may be securely attached to ground or the landing zone  195 . The stop  184  further comprises an unlocking structure  186  extending vertically upwards from the stop. The top of the unlocking structure  186  is configured to engage the lip  328  of the pin as the ring structure  310  descends to that height, and completely remove the lower portion  326  of the pin from the upper and lower bores  324   a  and  324   b  by the time the ring structure descends to the top of the stop  184 . This unlocks the ring structure  310 , allowing it to be opened and be removed from the pole structure  180 . 
     While the invention has been described in connection with various embodiments, it will be understood that the invention is capable of further modifications. This application is intended to cover any variations, uses or adaptation of the invention following, in general, the principles of the invention, and including such departures from the present disclosure as come within the known and customary practice within the art to which the invention pertains.