Portable derrick system, apparatus and methods
AssigneeDun-Rite Hoisting LLC
InventorMichael Narcisco
Life of this patent
Estimating the term…
Abstract
A portable derrick system for use in hoisting and lowering loads at a plurality of job sites, comprising, in combination: a boom subassembly, a boom head subassembly, a mast support subassembly, a mast head subassembly, a load-carrying line, a winch capable of cooperating with said line, power means for driving the winch, means for pivoting the boom assembly, means for controlling said pivoting means, the foregoing elements of the invention capable of being transported by humans to elevated positions such as, without limitation, rooftops and terraces, and wherein the aforementioned are capable of repeated assembly and disassembly at a plurality of job sites and serving to facilitate the elimination of the need for a street-level crane.
Claims8
A portable derrick system for use in hoisting and lowering loads at a plurality of job sites, comprising, in combination:
- a mast base,
- a mast removably interconnected to the mast base at a first lower end and extending vertically upwardly from the mast base,
- a multiple-sectioned boom assembly comprising a plurality of interlocking boom sections slidably connected to each other with a plurality of connecting pins, the plurality of interlocking boom sections comprising a smaller boom section, a larger boom section, and a largest boom section,
- a boomhead assembly,
- a masthead sheave assembly,
- wherein the masthead sheave assembly is removably interconnected to the largest boom section at a first end of the boom assembly and the boomhead assembly is removably interconnected to the smaller boom section at a second end of the boom assembly,
- and wherein the mast is removably interconnected at a second upper end to the first end of the boom assembly,
- a piston/cylinder assembly in which a piston is slidably engaged within the cylinder,
- a piston/boom connecting assembly removably and pivotally interconnecting a first end of the piston/cylinder assembly to the boom assembly,
- a piston/base connecting assembly removably interconnecting a second end of the piston/cylinder assembly to the mast, and
- a winch assembly removably interconnected to and supported by the piston/base connecting assembly, the winch assembly comprising a winch cable wound around a spool and which, when unspooled therefrom, extends around first roller bearing sheaves mounted on the masthead sheave assembly, along the boom assembly, and around second roller bearing sheaves mounted on the boomhead assembly, wherein a load-carrying hook is interconnected to an end of the winch cable for supporting a load therefrom.
Dependencies are inferred from the claim text.