Fire escape – ladder – or scaffold – Chute or escape tower for personnel
Reexamination Certificate
2002-05-21
2003-07-29
Lev, Bruce A. (Department: 3634)
Fire escape, ladder, or scaffold
Chute or escape tower for personnel
C182S049000, C182S071000, C187S414000
Reexamination Certificate
active
06598703
ABSTRACT:
BACKGROUND
1. Field of Invention
This invention relates to an apparatus for the emergency evacuation of people from high-rise buildings during fires, earthquakes, terrorist attacks and other disasters. The horrific events of Sep. 11, 2001 at the World Trade Center (WTC) surpassed all previous high-rise tragedies in terms of destruction and loss of life. The excessive amount of time and effort required to go down accessible emergency stairwells of the WTC carried severe consequences. Moreover, the global media coverage that televised trapped individuals jumping from the WTC towers tortuously renewed a long felt, long existing and still unsolved need. That need is for a quick, efficient, relatively inexpensive, practical, reliable and safe means of enabling even elderly, injured or disabled persons to either escape entrapment from or to bypass the levels of a high-rise building that is impassable due to flame, smoke or heavy damage with very little effort or assistance.
2. Description of Prior Art
There are known numerous devices used on aircraft, sea vessels and buildings for emergency evacuations to prevent or minimize injury or death resulting from fire, earthquakes, crashes, terrorism or other tragic events.
U.S. Pat. No. 3,973,644 discloses a chute and lowering device that is excessively complicated and lacking in versatility to easily support the swift evacuation of a great number of people.
U.S. Pat. Nos. 3,348,630, 4,099,595 and 4,099,596 disclose chutes as emergency evacuation devices. Disclosed are chute systems where the rate of deceleration of vertical drop is achieved by applying local braking elements that lessen the rate of descent by a person using the same. The rate of descent is fast and sudden between braking elements. Under very stressful circumstances a person, even with prior training on the device, cannot be reasonably expected to consistently employ these local braking elements correctly without sustaining injury.
U.S. Pat. No. 4,778,031 discloses a device that has an outer heat shield and an inner chute for controlled descent. However, individuals of various sizes are not easily supported, as the expansion is limited to an expansion joint. The overall design detracts from a building's aesthetics.
U.S. Pat. No. 5,320,195 discloses an emergency chute that uses bands of Spandex to provide a controlled rate of descent via elastic properties of the material. Generally however, it has similar disadvantages as those in U.S. Pat. No. 4,778,031.
U.S. Pat. No. 5,871,066 discloses a frame for an escape chute that does not take into account the panic that may be expected during emergency situations. Individuals may inadvertently push others beyond the frame into free fall. The frame's ledgebased design does not allow easy initial access for injured, disabled, elderly or unconscious individuals. Moreover, if used in multistory structures, the frame's placement fails to consider fear of heights and overestimates the capacity of ordinary individuals to undertake the physical act of going over a safe ledge from an extreme altitude. Finally, the frame is in very close proximity to the building. Thus, evacuees are still dangerously close to fire and smoke. If the frame is attached onto a ledge that is of flammable material, the frame may break free and plummet to the ground, and possibly hit people below.
U.S. Pat. No. 6,098,747 discloses a single chute which is knit-weaved, that combines thermal material such as Treveria FR (™) or a polyamide such as Kevlar (™) and an elastic material such as Spandex (™). It erroneously assumes that the combination of the thermal and elastic qualities of these two materials into a single knitwoven fabric can transfer each material's characteristics to the other. The dangerous consequences of this incorrect assumption have significantly influenced the design of the present invention. The following detailed elaborations are deemed essential:
The vertical Kevlar (™) component of the knit woven material is not likely to acquire the elasticity of the horizontal Spandex (™) component. Since the application of the rescue chute calls for the knit woven fabric to be wrapped, clamped and fastened around a frame and that the weight of several individuals must be supported by the same knit woven fabric, a risk factor must be pointed out, that is, the Kevlar (™) component of the rescue chute can suddenly snap or break.
The assertion as to the fragility of Kevlar when specifically applied in U.S. Pat. No. 6,098,747 rescue chute, is supported by knowledgeable individuals who have reported their findings through several websites. A hang gliding website's preflight inspection webpage clearly states: http://www.bigairparagliding.com/Tipsdetall.cfm?Title=Glider% 20Inspections “If your glider has Keviar lines, you can expect to replace them periodically. The reason for this is that Kevlar has “memory”, or is “knot sensitive”. This means that weak points develop where the line has been looped, tied, bent, or knotted for any reason.”
Again, a webpage discussing Kevlar's lack of elasticity and resulting weakness is cited in a motorcyclist's apparel website. It is mentioned that:
http://www.aerostich.com/isroot/riderwearhouse/DirectPages/straightstory.htmls “. . . believe it or not, pure Kevlar® fabric actually is much less abrasion-resistant than Cordura nylon. Kevlar® fibers have far less elasticity than Cordura® nylon fibers, a crucial handicap in a crash. Even the smoothest pavements have a rough aggregate surface that causes abrasive pulling. Nylon's stretchy fibers will elongate, ride over the surface irregularities, then snap back into the weave (like a tree bending in a strong wind), but Keviar® fibers quickly reach their tensile limit and snap.”
Another webpage clearly mentioning Kevlar's tendency to break suddenly may be found at the following archery enthusiast's website. It is mentioned that:
http://www.alansarchery.pwp.blueyonder.co.uk/Equipment/Strings/Strings.htm “These LCP's were important in their day, especially Kevlar. They still have important uses outside of archery, but have been replaced for our purposes by newer, more reliable fibres. There are still plenty of spools of Keviar and other aramids knocking around in cupboards and tackle boxes, but they should not be used. Even when new they have a short life—often as low as 1000 shots—and tendency to break without warning. After a few years storage, especially in sunlight, they could be positively dangerous.”
The horizontal Spandex (™) component of the knitwoven material will not suddenly gain the fire-resistant qualities of the vertical Kevlar (™) component. The knit-woven material will be progressively consumed by flame. The motorcyclist's apparel website at the following webpage explains this statement saying that:
http:/Iwww.aerostich.com/isroot/riderwearhouse/DirectPages/straightstory.html “To solve these problems, manufacturers blend Kevlar® with Lycra® and nylon. In this blend, “Kevlar®” is only about one third actual Kevlar®. This creates problems. Because of the additional nylon and Lycra®, much of its slight weight advantage over Cordura® is lost. It also loses some of its fireresistant qualities. The blended Kevlar® fabric may bum or melt Oust like nylon) when it comes in contact with a flame, hot component, or high frictional heat.”
As designed, the rescue chute of U.S. Pat. No. 6,098,747 can only be accessed where the frame is located and limited only to one story at a time. In case another evacuee needed to deploy another rescue chute immediately below the first one, it would not be possible. To increase the number of evacuees across several stories therefore, horizontal deployment of several rescue chutes of varying lengths would be required, but this can be a severe limitation during emergencies. Furthermore, no attempt is made to properly space evacuees apart, to prevent bodily contact, or to avoid collisions from occurring when several evacuees travel down the rescue chute.
Finally and more important
LandOfFree
Externally concealable, modular high-rise emergency... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Externally concealable, modular high-rise emergency..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Externally concealable, modular high-rise emergency... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3019100