Knotless security device

Abstract

A self-contained knotless security device and method for adjustably securing rope-style pilot ladders and debarkation ladders from any rung to ship deck lashing points, the device not relying on additional mechanical fittings or knot-tying skills. The device comprising a section of multi-strand polyester rope comprising an integrated polyolefin core and having a ship end and a ladder end, the ship end comprising a rugged, wear and corrosion-resistant thimble eye or shackle and the ladder end comprising a flexible long soft eye on the other end. The method comprising encircling ladder suspension members with the device and securing the device to the ship deck lashing point. Alternate polyolefin core construction provides tailored performance characteristics.

Claims

1. A method for securing a marine ladder to a ship using at least two Knotless Security Devices, the Knotless Security Device comprising: a length of multi-strand polyester rope having a ship end and a ladder end, the multistrand polyester rope comprising at least one polyolefin strand core, the ship end comprising a thimble eye, and the ladder end comprising a long soft eye, the method comprising: encircling one of the two marine ladder's side ropes below a step of the marine ladder with a first Knotless Security Device, inserting the ship end of the first Knotless Security Device through the long soft eye of the ladder end of the first Knotless Security Device, securing the ship end of the first Knotless Security Device to the ship, encircling the second of the two marine ladder's side ropes below the step of the marine ladder with a second Knotless Security Device, inserting the ship end of the second Knotless Security Device through the long soft eye of the ladder end of the second Knotless Security Device, and securing the ship end of the second Knotless Security Device to the ship.

2. The method for securing a marine ladder to a ship using at least two Knotless Security Devices of claim 1 wherein securing the ship ends of the first and second Knotless Security Devices to the ship comprise: locating and coupling a first and a second shackle through the thimble eyes of the first and second Knotless Security Devices respectively and to the ship respectively.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates a typical pilot ladder with integrated lashings.

(2) FIG. 2 illustrates the tie-off arrangement of a pilot ladder to a ship deck pad.

(3) FIG. 3 illustrates an embodiment of the invention.

(4) FIGS. 4A and 4B illustrate the preferred embodiment of the rope element.

(5) FIG. 5 illustrates an alternate embodiment of the invention.

(6) FIG. 6 illustrates pilot ladder suspension members secured by the invention.

(7) FIG. 7 illustrates steps in deployment of the invention.

DETAILED DESCRIPTION OF THE INVENTION

(8) The accompanying drawings illustrate example embodiments of the invention and its concepts. The drawings are not to scale. The terms and language used herein is for the purpose of describing particular aspects of the invention and is not intended to be limiting of the invention.

(9) As shown in FIG. 1, a typical pilot ladder (200) has tie off lashings (211) and (212) integrated as extensions of the suspension members (210) and (220). While some pilot ladders (200) have four ten-foot extensions (212), two on each side, as lashings, most have one ten foot (212) and one short thimble eye-spliced lashing (211) on each side. In this arrangement, FIG. 2 illustrates properly tied off lashings (211) and (212), when the pilot ladder (200) is of the correct length for the ship. The ten-foot lashing (212) is passed through the ship deck pad (55) and looped back through the short thimble eye-spliced lashing (211), then passed again through the ship deck pad (55) and looped back through the short thimble eye-spliced lashing (211) a second time before being tied off. If the ladder (200) possesses only the ten-foot extensions (212), the tie off must be done using the un-spliced lashings (212), without the double loop back arrangement.

(10) In either case, since the lashings (211) and (212) are integrated into a compliantly manufactured pilot ladder (200), the strength of the lashings (211) and (212) can be assured. However, tying large diameter rope such as ¾-inch rope is difficult, and depending upon the skill of the person involved, there could be any number of ways in which the ladder (200) might be tied off. Therefore, there is risk in the tie off being effectively performed.

(11) In addition, if one needed to shorten the ladder (200) for example, the pilot ladder integrated lashings (211) and (212) are of no use to affect a proper tie off to the ship. In this scenario, separate stopper ropes necessary to bridge the gap between the desired ladder suspension point and the ship deck pad (55) must be found. This presents the added risk of the stopper ropes not possessing adequate strength or performance characteristics for safe deployment of the pilot ladder (200) on top of the risk of an ineffective tie off due to inferior skills.

(12) Referring to FIG. 3, the Knotless Security Device (10) may be comprised of a length of multi-strand rope (100) having a ship end (20) and a ladder end (30). The preferred type of the rope (100) is three strand polyester rope as it has excellent load and wear performance, provides good stretch resistance, which mitigates bounce that contributes to individual instability during use, is soft to the hand yet provides for a firm grip even while wet, and provides for extended lifetime in the open sea environment.

(13) FIG. 4A and FIG. 4B illustrate the structure of the polyester rope as may be used in the instant invention. Commonly available polyester rope is comprised of multiple strands (101), three shown, twisted into a length of rope. Each strand (101) is made of multiple twisted spun polyester threads (102). When used for pilot ladders, a contrasting colored core must be included in the rope. Polypropylene is usually used due to cost and easy availability. However, in one embodiment of the instant invention, at least one polyolefin strand (103), two shown, each constructed of multiple twisted polyolefin threads, is included as a core within each strand (101) to provide superior strength and preserve flexibility, which translates into better stability in ladder tie-off.

(14) In the preferred embodiment of the Knotless Security Device (10), the multi-strand rope (100) includes two polyolefin strands (103) within each polyester strand (101) of the multi-strand rope (100) as depicted in FIGS. 4A and 4B. In this embodiment, the polyolefin-reinforced Knotless Security Device (10) provides pilot ladder-compliant strength that would normally require larger-diametered, less flexible stranded rope. The polyolefin strands (103) may also comprise blended polyolefin strands, including polyethylene, that provide superior performance characteristics when compared to polypropylene.

(15) The ship end (20) of the Knotless Security Device (10) comprises a thimble eye (25). As the primary anchor to the ship, it potentially encounters sharp forces that could tear or otherwise compromise an alternately constructed eyelet. Consequently, the thimble eye (25) requires a rugged, wear and corrosion-resistant eye that is easy to connect with a shackle or similar device to a ship's deck pad (55) or other anchor point, which may consist of moorings, hooks, turnbuckles and other common ship attachment articles. The preferred embodiment of the thimble eye (25) comprises a rope thimble (50) and a multi-tuck splice (110) binding the ship end (20) of the multi-strand rope (100) looped back securely around the thimble (50) to the multi-strand rope (100), thus securing the rope thimble (50) thus comprising the thimble eye (25). The is referred to as a thimble splice. In the preferred embodiment, the rope thimble (50) is comprised of 316 stainless steel in order to withstand the corrosive environment of the open sea.

(16) In an alternate embodiment the ship end (20) of the Knotless Security Device (10) comprises a shackle (51), see FIG. 5. The advantage of this arrangement is the complete elimination of any further required intervening mechanical devices between the pilot ladder (200) and the ship deck pad (55) when the invention is used.

(17) The preferred embodiment of the ladder end (30) comprises a long soft eye (35) that is capable of encircling a pilot ladder side rope (210) or (220), as seen in FIG 6. The preferred embodiment of the long soft eye (35) comprises a multi-tuck splice (110) binding the ladder end (30) of the multi-strand rope (100) looped back to the multi-strand rope (100). This is referred to as an eye splice. The ladder end (30) of the Knotless Security Device (10) serves as an easily assembled secure tether-type of arrangement that is flexible at the point of attachment and does not impart excessive wear or concentrated loads on the ladder (200) or any ladder elements. Flexibility is important as not all pilot ladders share the same construction. The Knotless Security Device (10) is configured such that it may easily capture virtually any pilot ladder (200) at any height without disassembly, modification or physically compromising the ladder.

(18) The preferred embodiment of the multi-tuck splices (110) on both the ship end (20) and the ladder end (30) of the Knotless Security Device (10) comprises five tucks and a length of shrink-wrap tube (60) securely surrounding at least a portion of the tucks of the multi-tuck splices (110) beginning at the end of the tucks in order to contain the loose ends of the rope strands over the course of usage. FIG. 3 depicts typical eye splice arrangements (110), which are used in the invention.

(19) In the best mode, referencing FIG. 7, a user secures a marine ladder to a ship by using at least two Knotless Security Devices (10). In STEP #1 and STEP #2 the user starts by encircling one of the two marine ladder's side ropes (210) below any step (230) of the marine ladder (200) with a first Knotless Security Device (10), then in STEP #3 and STEP #4 inserts the ship end (20) of the first Knotless Security Device (10) through the long soft eye (35) of the first Knotless Security Device (10) and pulls to tighten the long soft eye (35) around the marine ladder side rope (210), then secures the ship end (20) of the first Knotless Security Device (10) to the ship. Similarly, the user then encircles the second of the two marine ladder's side rope (220) below the same step (230) of the marine ladder (200) with a second Knotless Security Device (10), then inserts the ship end (20) of the second Knotless Security Device (10) through the long soft eye (35) of the second Knotless Security Device (10), and then secures the ship end (20) of the second Knotless Security Device (10) to the ship.

(20) The user easily secures the ship ends (20) of the Knotless Security Devices (10) to the ship's attachment points with a simple shackle or similar device commonly found on ships, thus not requiring any knots to be tied.

(21) In the alternate embodiment where the ship end (20) of the Knotless Security Device (10) comprises a shackle (51) as shown in FIG. 5, the user easily secures the ship ends (20) of the Knotless Security Devices (10) directly to the ship's attachment points, thus not requiring any knots to be tied or any compliant mechanical fittings to be located.

(22) It will readily be apparent to those skilled in the art that other applications are possible for the present invention, and while the embodiments described herein are illustrative of the invention, other modes of implementation are both within the spirit and scope of the invention.