Rope Structures and Rope Displacement Systems and Methods for Lifting, Lowering, and Pulling Objects

Abstract

A rope structure contains first and second sets of fibers. The first set of fibers is twisted together. The second set of fibers is twisted around the first set of fibers to form yarns. The first set of fibers is formed of a first material, the second set of fibers is formed of a second material, and elongation of the first set of fibers is different from elongation of the second set of fibers. Twists applied to the first and second fibers are such that loads on the rope structure are substantially evenly distributed across individual fibers. The yarns are combined to form strands in the form of a 3-strand rope. The strands are combined using a single braid process to form the rope structure defining a void space. The rope structure is formed such that lengths of fibers in the first and second sets are approximately the same.

What is claimed is: 
     
         1 . A rope structure comprising:
 first and second sets of fibers, where
 the first set of fibers is twisted together, 
 the second set of fibers is twisted around the first set of fibers to form a plurality of yarns, 
 the first set of fibers is formed of a first material, the second set of fibers is formed of a second material, and elongation of the first set of fibers is different from elongation of the second set of fibers, and 
 twists applied to the first and second fibers are determined such that loads on the rope structure are substantially evenly distributed across individual fibers forming the rope structure; 
   the plurality of yarns is combined to form strands in the form of a 3-strand rope;   the plurality of strands are combined using a single braid process to form the rope structure defining a void space; and   the rope structure is formed such that lengths of fibers in the first and second sets are approximately the same.   
     
     
         2 . A rope structure as recited in  claim 1 , in which the rope structure has a strand/rope ratio of approximately between 0.33 and 0.40. 
     
     
         3 . A rope structure as recited in  claim 1 , in which the fibers are formed from at least one material selected from the group consisting of polyamide (PA), polyethylene terephthalate/polyethersulfone (PET/PES), polypropylene (PP), polyethylene (PE), high modulus polyethylene (HMPE), liquid crystal polymer (LCP), Para-Aramid, and poly p-phenylene-2,6-benzobisoxazole (PBO) fibers. 
     
     
         4 . A rope structure as recited in  claim 1 , in which the fibers are formed from high modulus polypropylene (HMPP). 
     
     
         5 . A rope structure as recited in  claim 1 , in which at least one of the fibers, the yarns, and the strands are configured substantially to reduce a volume of the void space and thereby maintain a shape of the rope structure when the rope structure is under load. 
     
     
         6 . A rope structure as recited in  claim 1 , in which the yarns forming the strands are combined using one of a twisting process and a braiding process. 
     
     
         7 . A rope structure as recited in  claim 1 , in which the rope structure has a strand/rope ratio of approximately between 0.35 and 0.38. 
     
     
         8 . A method of forming a rope structure comprising the steps of:
 providing first and second sets of fibers, where the first set of fibers is formed of a first material, the second set of fibers is formed of a second material, and elongation of the first set of fibers is different from elongation of the second set of fibers;   twisting the first set of fibers together;   twisting the second set of fibers around the first set of fibers to form a plurality of yarns such that such that loads on the rope structure are substantially evenly distributed across individual fibers forming the rope structure;   combining the plurality of yarns to form strands in the form of a 3-strand rope;   combining the plurality of strands using a single braid process to form the rope structure defining a void space such that lengths of fibers in the first and second sets are approximately the same.   
     
     
         9 . A method as recited in  claim 8 , further comprising the step of forming the rope structure to have a strand/rope ratio of approximately between 0.33 and 0.40. 
     
     
         10 . A method as recited in  claim 8 , in which the step of providing the first and second sets of fibers comprises the step of forming the fibers in the first and second sets of fibers from at least one material selected from the group consisting of polyamide (PA), polyethylene terephthalate/polyethersulfone (PET/PES), polypropylene (PP), polyethylene (PE), high modulus polyethylene (HMPE), liquid crystal polymer (LCP), Para-Aramid, and poly p-phenylene-2,6-benzobisoxazole (PBO) fibers. 
     
     
         11 . A method as recited in  claim 8 , in which the step of providing the first and second sets of fibers comprises the step of forming the fibers in the first and second sets of fibers from high modulus polypropylene (HMPP). 
     
     
         12 . A method as recited in  claim 8 , further comprising the step of configuring at least one of the fibers, the yarns, and the strands substantially to reduce a volume of the void space and thereby maintain a shape of the rope structure when the rope structure is under load. 
     
     
         13 . A method as recited in  claim 1 , in which the step of combining the yarns to form the strands comprises the step of using one of a twisting process and a braiding process. 
     
     
         14 . A method as recited in  claim 8 , further comprising the step of forming the rope structure to have a strand/rope ratio of approximately between 0.35 and 0.38.