Method of lowering and raising loads by means of a jack assembly and lifting element

Abstract

In a method of lowering and raising loads by means of a jack assembly and lifting element the load is transferred from the lifting element by supporting means disposed on the lifting element and having a cross-section considerably larger than that of the lifting element. The supporting means are alternately carried by preferably dismountable carrying members with holes for the lifting element, which holes are smaller than the cross-section of the supporting means, the carrying members being mounted on relatively movable parts of the jack assembly.

I claim: 
     
       1. A method of lowering and raising a load by means of a jack assembly and lifting element, which comprises transferring the load from the lifting element by supporting means moveable along said lifting element and alternately carrying the supporting means by one-and-then the other of two carrying means having holes accommodating the passage of the lifting element, with said carrying means being mounted on .[.relatively moveable.]. parts of the jack assembly .Iadd.which are moveable relative to each other.Iaddend., and said lifting element being joined in series with other lengths of lifting element by connectors of a size incapable of passing through the holes of the carrying means .Iadd.and of a length substantially less than that of any one length of lifting element.Iaddend., and alternately dismounting the .[.carrier.]. .Iadd.carrying .Iaddend.means to permit free passage of the connectors .Iadd.upwards and downwards .Iaddend.and thus .Iadd.to permit free passage of .Iaddend.the joined lengths of the lifting element. .Iadd. 2. A method of lowering and raising a load by means of a jack assembly and lifting element, which comprises transferring the load from the lifting element by supporting means moveable along said lifting element and alternatively carrying the supporting means by one-and-then the other of two carrying means having holes accommodating the passage of the lifting element, with said carrying means being mounted on parts of the jack assembly which are moveable relative to each other, and said lifting element being joined in series with other lengths of lifting element by connectors of a size incapable of passing through the holes of the carrying means and of a length substantially less than that of any one length of lifting element, and alternately dismounting said carrying means to permit free passage of said connectors upwards and downwards. .Iaddend. .Iadd. 3. The method of claim 2, wherein the carrying means are mounted on relatively movable parts of the jack assembly in optional upper or lower positions, the choice of position being determined by the place where the joining pieces are situated. .Iaddend..Iadd. 4. The method of claim 3, wherein the relatively movable parts of the jack assembly on which parts the carrying means are mounted consist of a piston unit of the jack and of a spacing means co-operating with a fixed part of said jack. .Iaddend..Iadd. 5. The method of claim 3, wherein the relatively movable parts of the jack assembly on which parts the carrying means are mounted, are piston units of at least two co-operating jacks. .Iaddend. .Iadd. 6. A method of lowering and raising a load by means of a lifting element and a jack assembly having load bearings parts; said method comprising the steps of: (a) transferring the support for a load carried by said lifting element from a first to a second supporting means which are movable along said lifting element and which may be fixed with respect to said lifting element at different positions therealong, carrying said first supporting means by a first carrying means to effect movement of the load, and thereafter carrying said second supporting means by a second carrying means to support the load so that said first carrying means and supporting means are free of load and may be moved relative to said lifting element; both said carrying means being provided with holes accommodating the passage of said lifting element therethrough and being removably mounted on said load bearing parts of said jack assembly; and   (b) physically removing and remounting the carrying means which is free of load while the other of said carrying means is carrying its respective supporting means, to permit free passage of said supporting means upwards and downwards with respect to said lifting element. .Iaddend. .Iadd. 7. The method of claim 6 where said lifting element is joined in series with other lengths of lifting elements, by connectors of larger cross-section than that of said lifting elements; said load bearing parts of said jack assembly being provided with apertures to permit the passage of said connectors and supporting means therethrough. .Iaddend..Iadd. 8. The method of claim 6 where said lifting element is substantially centrally located in said jack assembly. .Iaddend..Iadd. 9. The method of claim 6 wherein said first carrying means is mounted above said second carrying means, the arrangement being such that said connectors do not interfere with the removing and remounting of said carrying means which is free of load when lowering and raising a load. .Iadd. 10. The method of claim 6 wherein said load bearing parts of said jack assembly on which said first and second carrying means are mounted consist of a piston unit of said jack assembly and a spacing means in fixed engagement with a fixed portion of said jack assembly so that said piston unit is movable with respect to said spacing means. .Iaddend..Iadd. 11. The method of claim 6 wherein said load bearing parts of said jack assembly on which said first and second carrying means are mounted are piston units of at least two co-operating jack assemblies.