Patent ID: 7299589

Claim:
A telescoping boom structure comprising a plurality of tubular boom sections having respectively different diameters, and being concentrically nestable about a common displacement axis, and having helical tracks and roller assemblies through which adjacent tubular boom sections mutually engage one another for telescoping displacement along said common displacement axis, wherein a first tubular boom section has a helical track formed along an exterior tubular surface thereof, so as to be engageable by one or more rotational elements retained at an interior surface of a second tubular boom section having a diameter greater than that of said first tubular boom section, wherein adjacent ones of said concentrically nestable tubular boom sections are mutually engageable with one another by means of said helical tracks formed on outer cylindrical surfaces of relatively radially interior tubular boom sections, and associated rollers formed on inner surfaces of relatively radially exterior tubular boom sections and being arranged to ride along said helical tracks.