Equipment for excavating solid surfaces or floors, such as made of asphalt or concrete or similar solid materials, for example, in particular for digging trenches in said solid surfaces or floors, said equipment comprising a main supporting frame and rotatable working or digging means rotationally fixed to said main supporting frame, a power source for actuating said working or digging means and fixed to said main supporting frame, and an adjustment frame defining at least one substantially flat contact portion adapted to be placed in contact with a corresponding portion of the surface to be worked; wherein said adjustment frame comprises a first guiding slot through which at least one portion of said power source extends, said power source being translatable within said first slot, said adjustment frame being thus translatable with respect to said main supporting frame, wherein the translation of said adjustment frame is defined by the reciprocal engagement of said at least one portion of said power source and said first guiding slot; wherein said power source defines a longitudinal extension axis and in that said adjustment frame is rotatable about said main supporting frame with respect to said longitudinal extension axis of said power source, characterized in that said equipment comprises adjustment means adapted to allow to adjust the position of said adjustment frame with respect to said main supporting frame so as to allow to adjust the working depth of said working means, said main supporting frame and said adjustment frame are furthermore reciprocally fixed by means of an engagement pole or pin extending in a direction substantially parallel to said longitudinal extension axis of said power source, wherein said engagement pole or pin engages a second engagement slot, wherein said second engagement slot is formed in said adjustment frame and wherein said second engagement slot extends along an arc-shaped or semi-circular development or path centered on said longitudinal extension axis of said power source, said engagement pin or pole being thus translatable along said second engagement slot on a plane which is substantially perpendicular to said longitudinal extension axis of said power source; wherein said adjustment means comprise a fixing arm rotationally fixed to said main supporting frame by means of which said adjustment frame is fixed to said main supporting frame, so that, by rotating said fixing arm about the rotation axis thereof in two opposite rotation directions, a translation of said adjustment frame is obtained with respect to said main supporting frame in two opposite translation directions, respectively, wherein said fixing arm is shaped as a class 1 lever, wherein said adjustment frame is rotationally fixed to a first end portion of said fixing arm which comprises the point of application of the resistance of said lever, wherein said engagement pole or pin extends from said first end portion of said fixing arm in a direction perpendicular to the rotation plane of said arm, the end portion of said pole or pin opposite to said arm being engaged in said second engagement slot of said adjustment frame. said equipment comprises adjustment means adapted to allow to adjust the position of said adjustment frame with respect to said main supporting frame so as to allow to adjust the working depth of said working means, said main supporting frame and said adjustment frame are furthermore reciprocally fixed by means of an engagement pole or pin extending in a direction substantially parallel to said longitudinal extension axis of said power source, wherein said engagement pole or pin engages a second engagement slot, wherein said second engagement slot is formed in said adjustment frame and wherein said second engagement slot extends along an arc-shaped or semi-circular development or path centered on said longitudinal extension axis of said power source, said engagement pin or pole being thus translatable along said second engagement slot on a plane which is substantially perpendicular to said longitudinal extension axis of said power source; wherein said adjustment means comprise a fixing arm rotationally fixed to said main supporting frame by means of which said adjustment frame is fixed to said main supporting frame, so that, by rotating said fixing arm about the rotation axis thereof in two opposite rotation directions, a translation of said adjustment frame is obtained with respect to said main supporting frame in two opposite translation directions, respectively, wherein said fixing arm is shaped as a class 1 lever, wherein said adjustment frame is rotationally fixed to a first end portion of said fixing arm which comprises the point of application of the resistance of said lever, wherein said engagement pole or pin extends from said first end portion of said fixing arm in a direction perpendicular to the rotation plane of said arm, the end portion of said pole or pin opposite to said arm being engaged in said second engagement slot of said adjustment frame.