Device (1) for improving a cavity (8), particularly a cavity in a porous material, bored having hollow spaces uncovered by the cavity, comprising an element (2) to produce or coupling mechanical energy, and a sleeve ( 4) cylindrical with a cylindrical lateral surface with an outer diameter and a cavity (26) center for receiving a guide (3) pin, a guide (3) pin and amelioration sleeve (6), the pin being configured guide ( 3), before the application of mechanical energy, substantially so insertable to the bottom of the cavity (8) being enclosed guide (3) shank, in the region of its end facing the bottom of the cavity by the amelioration sleeve (6) consists of a liquefiable material with mechanical energy, wherein the cylindrical side surface of the amelioration sleeve (6) substantially the same outer diameter as the sleeve (4), the guide pin being housed (3 ) In the central cavity (26) slidably so that the mechanical energy applied the sleeve (4) can slide relative to the guide (3) towards spike towards the bottom of the cavity (8) under the liquification and / or longitudinal displacement of the material of the amelioration sleeve (6), the sleeve (4) at its distal end an edge (5, 48) distal circumferential tapering towards it, said edge (5, 48) being configured or either straight and therefore conical or curved shape, especially concave or convex, said edge (48) distal to the transition of the step being provided if the sleeve (4) is arranged radially staggered at its distal end.Dispositivo (1) para mejorar una cavidad (8), especialmente una cavidad en un material poroso, agujereado que presenta espacios huecos descubiertos por la cavidad, el cual comprende un elemento (2) para producir o acoplar energía mecánica, así como un manguito (4) cilíndrico con una superficie lateral cilíndrica con un diámetro exterior y con una cavidad (26) central para alojar una espiga guía (3), una espiga guía (3) y un casquillo de mejora (6), estando configurada la espiga guía (3), ante
