US 3116948 A
Description (OCR text may contain errors)
Jan. 7, 1964 E. c. ELSNER 3,116,943
WEBBING RING FOR CARGO SLING Filed July 25, 1962 INVENTOR. FIG. 1 EDWIN C. ELNER United States Patent 3,116,948 WEBBIWG RING FOR CARGO SLlNG Edwin C. Eisner, Pasadena, Calif, assignor to Aeroqnip Corporation, Jackson, Mich a corporation of Michigan Filed July 25, 1962, Ser. No. 212,344 4 Claims. (Cl. 29474) The invention pertains to a cargo sling and particularly relates to a cargo sling of the aerial type which may be employed with helicopters and the like for carrying suspended external loads.
The present invention is an improvement of the sling shown in the presently pending US. patent application of Albert R. Molzan et al., Serial No. 118,680, which has the same assignee as the instant application, filed June 21, 1961, and reference thereto is incorporated herein.
The principal object of the present invention is to provide an improved lift ring which will sustain great loads.
More particularly the invention deals with a novel lift ring construction including an elongate strap of webbing wound in the form of a spiral and wherein the folded over ends of the strap are friotionally engaged between the turns of the spiral.
These and other objects of the invention arising from the details and relationships of the components of an embodiment thereof will be apparent from the following description and accompanying drawings wherein:
FIG. 1 is an assembly elevational view of a cargo sling in accord with the invention,
FIG. 2 is an enlarged detail view of the improved assembled ring member employed with the embodiment of FIG. 1,
FIG. 3 is a detail view of the ring member clevis taken along section IV-IV of FIG. 2.
The general appearance and relationship of the components of a cargo sling in accord with the invention is best shown in FIG. 1. The cargo sling basically consists of a ring member from which depend a plurality of leg members 12. The ring member 10 is adapted to be gripped by a hook or other means attached to the load supporting cable suspended from the helicopter or other supporting means. Usually automatic release means are employed with the helicopter cable which cooperate with the ring member wherein upon the suspended load being lowered to the ground the release means will automatically drop the sling. In the illustrated embodiment four leg members are shown as employed with a single ring; however, it will be appreciated that more or fewer leg members may be used if desired.
The ring member 10 is preferably formed from an elongated strap 14 of fabric webbing, preferably webbing formed of synthetic fibers of high strength such as nylon. It is desired to form a loop at each end of the ring strap 14 and to this end the ends 16 and 17 of the strap are folded back over on themselves and sewed at 18 and 19 to form loops 2% "and 21 respectively. The annular ring configuration is formed by spirally winding the strap 14 in the manner shown in FIG. 2 and a clevis 22 is inserted through the loops 2t and 21 to interconnect the ends of the strap. The nut and bolt 24, FIG. 3, is inserted through the ends of the clevis to complete the assembly of the ring.
It will be seen that the webbing ring 10 is wound in a spiral form so that the folded back ends 116 and 17 are entrapped and frictionally engaged between the turns of the webbing. It will also be seen that the lengths of the ends 1% and 17 approach the circumference of the ring 10. It has been found that a length of webbing is only as strong as the sewing. As a result, the entrapment and frictional engagement of the sewn ends of the strap greatly increases the strength of the ring. Of course, the
3,116,948 Patented Jan. 7, 1964 longer the ends 16 and 17, the greater the area of frictional engagement is enjoyed. It should be appreciated, however, that the lengths of the ends 16 and 17 can be varied within desired limits to suit the intended application of the device.
The leg members .12 each consist of two strands or portions which are also preferably constructed of high strength fabric webbing, such as nylon webbing. As shown in FIG. 1, the upper leg member portion is designated 26 and the lower leg member portion is designated by reference character 28. Leg portions 26 are formed at their outer or upper end with a loop 30 by folding the end of the leg portion back upon itself and sewing the same to the main leg, portion. The loops 30 circumscribe the ring member 10, FIG. 2, in a manner wherein the loops may be easily positioned upon the ring periphery. The inner end '32 of the leg portions 26 are attached to the adjustment buckle 34-, in the manner described in the aforementioned M-olzan application.
In assembling the leg portion 26 to the buckle, the end 36 is connected to the adjustable portion of the buckle and then inserted through a keeper 4t circumscribing the leg portion 26.
Thereupon, the end 36 is folded and sewed back upon itself to prevent the end from being pulled back through the keeper. A delta ring 42, is placed on the leg member portion 26 prior to the assembly of the leg portion to either the ring or buckle.
The lower leg portion 28 is provided with a loop 44 defined at its lower or outer end by folding the portion end back upon itself and sewing the end to the main portion body. A load attaching member consisting of a hook 46 in the disclosed embodiment, is affixed to the loop 44 by means of a bolt 48 passing therethrough. The inner or upper end of the leg portion 28 is also formed with a loop 5% by sewing the inner end back upon itself, and the loop 50 is connected to the buckle 34 by means of the bolt 52.
The construction of the buckle 34 and the adjustment of the leg portions is best shown and described in the referenced copending application of Molzan et al.
T o assemble the leg members '12 to the ring member 11 the ring will be in the elongated strap form and may be inserted through the loops 30 of the desired number of leg members. The ring member strap 14 is then wound in spiral fashion being inserted through the loops 30 upon each revolution of the end being wound. After the desired number of windings of the strap, the ring member will be formed and may be assembled by the use of the clevis 22 and bolt 24.
Should the load being carried be such that it is not de sired to attach the hooks 4-6 directly thereto, or to a cargo net, the books 46 may be inserted under the load and brought around and hooked upon the delta ring 42 of the associated leg member to lift the load. Also, in a circumstance where a very short leg member length is desired the hook 46 may be directly attached to the buckle 34 by the use of the bolt 48.
Should one of the leg members 12 become worn or damaged, the leg member may be quickly replaced merely by disassembling the ring member clevis 22 to disas semble the ring and place a new leg member thereon. Likewise, the ring strap, buckle and hooks may be easily replaced.
It will be appreciated that various embodiments of the invention may be apparent to those skilled in the art without departing from the spirit and scope thereof, and it is intended that the invention be defined only by the scope of the following claims.
1. A cargo sling particularly adapted for aerial use, comprising, in combination, a flexible ring member of high strength, light weight material, a plurality of elongated leg members of flexible, high strength, lightweight material, said leg members having one end attached to said ring member and load attaching means attached to the other end of said leg members, and adjusting srneans operatively associated with' each of said leg members intermediate the ends thereof for selectively varying the length of the leg members, said ring member being formed by an elongated strap having its ends folded back and secured to the adjacent portions of said strap thereby forminga loop at each end of said strap and being Wound in a spiral manner to form a. plurality of layers wherein said folded back ends are entrapped between adjacent layers, and means interconnecting. said loops.
2. The subject matter of claim 1 wherein said strap is 15 formed of webbed fabric and said folded over ends are sewn to the adjacent portions of said strap.
3. A ring member comprising an elongated strap having its ends folded back and secured to the adjacent portions of said strap thereby forming a loop at each end and being Wound in a spiral manner to form a plurality of layers wherein said folded back ends are entrapped between adjacent layers, and means interconnecting said loops.
4. The subject matter of claim 3 wherein the folded back ends of said strap are of a length equal to at least 10 one half the circumference of said ring member.
References Cited in the file of this patent UNITED STATES PATENTS