A coaxial screw gear sleeve mechanism comprising: a first member (110) and a second member (150) each having an inner surface configured to face the inner surface of the other； a first post and (111, 112, 511, 621, 721, 810) a second post each having a surface (113, 114, 113A, 114A, 113B, 114B, 811) threaded on a portion of the post； and a corresponding sleeve (120, 130, 520, 620, 720, 820) for each post configured to wrap the respective post and having: an inner surface (122, 132) threaded into a portion of the sleeve configured to interconnect directly with the threaded surface (113, 114, 113A, 114A, 113B, 114B, 811) of the pole； and an outer surface (124, 134, 134A, 822) helically engaged in a portion of the sleeve； and a drive mechanism having a surface configured to interconnect simultaneously with and actuate the meshed outer surface of each of the sleeves, arranged so that the selective operation of the drive mechanism causes a telescopic expansion of the first member (110) with respect to to the second member (150) by a simultaneous telescopic axial expansion of the first sleeve and the second sleeve that are moved relative to the drive mechanism and the first post and the second post that are moved relative to the first sleeve and the second sleeve, and wherein the second member defines a pair of threaded sleeve openings (161, 162) on the inner surface, each sized to rotatably accommodate one of the sleeves therein, and the second member further defines an opening (154) drive mechanism sized to rotatably contain the drive mechanism e n the same, and where the mechanism interconnects with the sleeves through the respective openings (157, 158) in the second member between the opening of the drive mechanism and the openings of the sleeve.Un mecanismo de manguito de engranaje de tornillo coaxial que comprende: un primer miembro (110) y un segundo miembro (150) teniendo cada uno una superficie interior configurada para mirar hacia la superficie interior de la ot
