Linear actuator particularly for sliding doors and for sliding doors and windows in general

1. A linear actuator, for sliding doors and for sliding windows, comprising

a supporting body,

a motor drive accommodated and fixed within said supporting body,

a driving gear adapted to be rotated within said supporting body by said motor drive about a rotation axis, and

a driven rack, adapted to be fixed to a sliding leaf, and having a longitudinal axis and being coupled to mesh with said driving gear such that said rotation axis of said driving gear extends parallel to said longitudinal axis of said driven rack,

said driving gear being constituted by an endless screw, a thread of which engages between oblique teeth of said driven rack, and

said supporting body being substantially tubular and telescopic in a direction that is parallel to said longitudinal axis of said driven rack and to said rotation axis of said driving gear, said supporting body being configured to substantially cover the driven rack when fully extended, and

a slider, said slider being fixed to said supporting body and configured to slide on said driven rack, wherein said rack has, at lateral long sides thereof, respective longitudinal grooves arranged laterally to said oblique teeth of said rack, which accommodate engagement and sliding tabs that protrude from the slider into said longitudinal grooves.

2. The linear actuator according to claim 1 , wherein said motor drive is constituted by an electric motor having a driving shaft, which supports the driving gear.

3. The linear actuator according to claim 1 , wherein said supporting body comprises a central part and at least one lateral portion which is extractable with respect to said central part.

4. A linear actuator arranged in a sliding door or sliding window, comprising

a supporting body,

a motor drive accommodated and fixed within said supporting body,

a driving gear adapted to be rotated within said supporting body by said motor drive about a rotation axis,

a driven rack, fixed to a sliding leaf of said sliding door or sliding window, and having a longitudinal axis and being arranged meshing with said driving gear such that said rotation axis of said driving gear extends parallel to said longitudinal axis of said driven rack,

said driving gear being constituted by an endless screw, a thread of which engages between oblique teeth of said driven rack, and

said supporting body being substantially tubular and telescopic in a direction that is parallel to said longitudinal axis of said driven rack and to said rotation axis of said driving gear, said supporting body being configured to substantially cover the driven rack when fully extended,

said supporting body being fixed at one end to a jamb of said sliding door or sliding window, and said supporting body being fixed at an opposite end by means of a slider, which is coupled so as to slide on the rack,

wherein said rack has, at lateral long sides thereof, respective longitudinal grooves arranged laterally to said oblique teeth of said rack, which accommodate engagement and sliding tabs that protrude from the slider into said longitudinal grooves.

5. The linear actuator in the sliding door or the sliding window according to claim 4 , wherein said rack is fixed to said sliding leaf by being glued or by means of threaded connections.

6. The linear actuator in the sliding door or the sliding window according to claim 4 , wherein said slider is fixed to the supporting body at the driving gear and has an opening adapted to allow the engagement of the thread of said driving gear with the rack.

7. The linear actuator according to claim 1 , wherein said slider is fixed to the supporting body by means of screws.