BRIEF DESCRIPTION OF THE DRAWINGS
The novel features believed characteristic of the invention are set forth in the appended claims. The invention itself, however, as well as a preferred mode of use, further objectives and advantages thereof, will be best understood by reference to the following detailed description of illustrative embodiments when read in conjunction with the accompanying drawings wherein:
FIG. 1 is plan view of one embodiment of the fall arrest lanyard showing the individual components of same;
FIGS. 2A-2B is a side view of the etrier shown in the folded, pre-deployment position;
FIG. 3A is a perspective view showing a worker with the fall arrest lanyard attached to a safety harness and attached to an anchor point;
FIG. 3B is a perspective view showing deployment of the fall arrest lanyard during a fall sequence;
FIG. 3C is a perspective view of the fall arrest lanyard with etrier fully deployed with the user suspended in the safety harness at the end of the fall sequence;
FIG. 3D is a perspective view of the fall arrest lanyard with the user placing his feet within the etrier to assume a comfortable rest position which prevents the onset of suspension trauma injury while awaiting rescue;
FIG. 4 is a plan view of a fall arrest lanyard showing a manually deployed etrier in accordance with an embodiment of the invention;
FIG. 5A is a perspective view showing a user with the fall arrest lanyard and manually deployed etrier attached to a safety harness and a self-retracting lifeline;
FIG. 5B is a perspective view showing a user suspended from a self-retracting safety line deploying the manually deployed etrier;
FIG. 5C is a perspective view showing a user climbing the manually deployed etrier; and
FIG. 5D is a perspective view showing a user lowering himself to the ground after performing a weight transfer using the manually deployed etrier.
DETAILED DESCRIPTION OF THE INVENTION
A preferred embodiment of the invention is disclosed herein as shown in FIGS. 1 through 3B. FIG. 1 shows the fall arrest lanyard 10 assembly in accordance with an embodiment of the present invention. In this embodiment, the lanyard assembly 10 is comprised of two upper straps 12 connected at one end via universal connectors of sufficient tensile strength, in this instance shown as clamp 20a, and two lower straps 14. Upper straps 12 and lower straps 14 are connected via sewn loops as shown in FIG. 1, although alternative connection devices may be utilized including universal clamps, lobster clamps and load bearing rings of requisite tensile strength. Upper straps 12 include a folded etrier 16 secured to each upper strap 12. Etrier packs 16 comprise a length of nylon strap with loops sewed therein that is folded and enclosed in a breakaway sheathing, such as shrink wrap. Etrier packs 16 are shown in the stored position wherein the etriers, a French term used by climbers to denote “step rope ladders,” are attached to upper straps 12 by stitching or other connection methods as known in the art. Shock packs 18 comprise a length of folded upper strap 12 which is enclosed in a breakaway sheathing material such as shrink wrap plastic. The sheathing material utilized with etrier packs 16 and shock packs 18 acts to keep the etriers and shock packs in a secure, folded position until the application of sufficient tensile force which overcomes the restrictive force of the sheathing and allows the etriers and shock packs to deploy during a fall sequence. Incorporated and secured to upper straps 12 are cinch buckles 24 which provide an additional attach point for securing tools or other objects as desired by the user. Clamps 20 are positioned at the terminal ends of lower straps 14 for attachment directly to anchor points such as retractable safety lines or fixed anchor components. Sliding buckles 22 are included on each of the lower straps 14 to facilitate attachment to the anchor system.
FIG. 2A shows the folded etriers 16 in greater detail in the “stored” position. In this position, the etrier pack 16 is shown folded and retained in the folded position by shrink-wrap type material sheathing 26. The etrier strap 28 is typically anywhere from four to six feet in unfolded length, although shorter or longer lengths may be utilized depending upon the specific application. Sheathing 26 retains the length of strap 28 in a folded state until sufficient tensile force exists between lower strap 14 and upper strap 12 thereby causing the etrier pack 16 to begin deploying along its length. As shown in FIG. 2B, as sufficient tensile force acts across upper strap 12 and lower strap 14, the sheathing 26 breaks away and provides a decelerative force as the etrier pack strap 27 pulls through the loop in the lower strap 14. The action of the strap 27 acts both to provide a declarative force and to deploy the etrier strap 28.
FIGS. 3A-3D represent a typical operation of the fall arrest lanyard described herein. In FIG. 3A, a user 30 is shown wearing safety harness 32 as is known in the art. Lanyard assembly 10 is connected to the user's harness 32 via clamp 20A. At least one end of the lanyard assembly 10 is anchored to a secure point such as static beam 34 or to an existing safety line (not shown). FIG. 3B shows the beginning of a fall sequence wherein user 30 has lost his or her footing and begins to fall. As tensile forces begin to act across the upper strap 12 and lower strap 14 of the lanyard assembly 10, the etrier pack 16 deploys. Thereafter, the development of increasingly greater tensile forces across the upper and lower straps of the lanyard assembly 10 triggers activation of the shock pack 18 to resistively release the folded portion of the upper strap 12 contained within the shrink wrap material resulting in the development of a decelerative force acting to slow the fall of the user 30. The user stops falling as the length of upper strap and lower strap is fully deployed.
FIG. 3C shows the user suspended above the ground after the fall scenario is complete. In this depiction, the weight of the user 30 causes the safety harness 32 with leg straps 33 to act as constriction points on the body of the user 30. This phenomena, known as “suspension trauma,” can act to constrict blood flow and decrease circulation which can lead to fatigue, unconsciousness and possibly death if the user is not quickly rescued. However, the deployed etrier 28 provides the user 30 with the ability to independently avoid suspension trauma. As shown in FIGS. 3C and 3D, the etrier 28 includes loops 29 into which the user 30 may insert his or her feet and assume a comfortable sitting or standing position while awaiting rescue and retrieval. This allows the user 30 to remove the pressure from remaining suspended in the harness 32 thereby preventing the onset of suspension trauma while awaiting rescue. Alternatively, the user can take advantage of the weight transfer capability of the manually deployed etrier to lower himself or herself to the ground using a rescue kit as discussed below with regard to an alternative embodiment of the invention.
Referring now to FIG. 4, a fall arrest lanyard 40 with a manually deployed etrier strap 28 in accordance with an embodiment of the invention as illustrated. In certain situations, the force created as a result of a fall by a user of a safety harness might not be sufficient to deploy the etrier pack discussed with regard to the automatically deployed etrier discussed above. Consequently, it may be desirable to have an etrier that may be manually deployed by the user in the event of a fall. In particular, the use of a self-retracting safety line (SRL) results in the safety line remaining taut while the user is working, for example, on the side of a building. In this situation, the user will be arrested immediately upon falling and will not typically gain enough momentum to deploy either an automatically deployed etrier or a shock pack as discussed above. The manually deployed etrier of FIG. 4 is constructed by sewing an etrier strap 28 to a cow tail strap. The cow tail strap is known in the art and is used to provide an extension to make it easier for the user to attach his or her harness to a lifeline. The distal end of the etrier strap 28 has a small ring 42 and tab 44 to provide a surface that may be easily grasped by the user to manually deploy the etrier strap 28. The etrier strap 28 is folded and a sheath 46 is placed around the folded etrier strap 28 in a manner similar to the manner in which the etrier strap on the automatically deployed etrier discussed above is stored.
FIG. 5A shows a perspective view of a worker with the manually deployed etrier 40 attached to the dorsal connection of the user's safety harness. The other end is attached to a self-retracting lifeline (SRL) 52.
FIG. 5B shows the user 30 deploying the etrier 28 by pulling the ring 42 and tab 44 after a fall. As he pulls the etrier, the sheathing 46 breaks and falls off allowing the etrier 28 to fully extend.
FIG. 5C shows the user climbing up the etrier after the etrier 28 has been deployed. As the user 30 climbs up the etrier 28, the user 30 can cause the tension in strap 54 to be released so that clamp 56 can be disconnected after a rescue line is attached to the user's harness or belt.
FIG. 5D shows the user descending to the ground using a rescue line attached to the clamp 58 at one end and the front of his harness (not shown) to allow the user 30 to lower himself to the ground. In this manner, the user 30 need not await a rescue.
The arrest lanyard and etriers disclosed herein can be manufactured from nylon or polyester materials and plastics as known in the art to sufficient specifications for all applicable OSHA and specific industry safety requirements, including requirements which meet or exceed OSHA 29 CFR 1926.502 and ANSI Z359.1-1992. These materials are abrasion resistant and display excellent durability in all operational environments. In an alternative embodiment, the fall arrest lanyard of the first embodiment disclosed herein may comprise a “single leg” lanyard which incorporates only one upper and lower strap with terminal connection points at the ends of the upper and lower straps, and which includes the shock pack and deployable etrier system disclosed herein.
Although the present invention has been described in terms of an exemplary embodiment, it is not limited to these embodiments and modifications. Alternative embodiments, modifications, and equivalents, which would still be encompassed by the invention, may be made by those of ordinary skill in the art, in light of the foregoing teachings. Therefore, the following claims are intended to cover any alternative embodiments, modifications, or equivalents which may be included within the spirit and scope of the invention defined by the claims.
Patent Application
20080060872
