Sanding machine for the sanding/finishing panels made of wood, metal, or the like

A sanding machine for sanding/finishing panels (2) made of wood, metal or the like, the sanding machine comprising a feeding device (4), which defines a support surface (P) for at least one panel (2) and is designed to feed the panel (2) in a first direction (5);

• a sanding device (10), which is mounted above the support surface (P) and comprises, in turn, an abrasive belt (11), which is wound in a ring shape around a plurality of idler rollers (12) so as to sand an upper face (18) of the panel (2);
• a plurality of thrust elements (20), which are distributed inside the abrasive belt (11) in a second direction (9), which is transverse to the first direction (5) and parallel to the support surface (P);
• and, for each thrust element (20), a respective actuator cylinder (22) to move the thrust element (20) between a lowered operating position, in which the thrust element (20) moves the abrasive belt (11) so as to cause it to come into contact with the upper face (18) of the panel (2), and a raised rest position;
• each actuator cylinder (22) comprising a cylinder (23), an output rod (27), which is engaged in the cylinder (23) in a sliding manner and is configured to divide the cylinder (23) into an upper chamber (30) and a lower chamber (31), a first pneumatic circuit (32) communicating with the upper chamber (30) so as to move the thrust element (20) to its lowered operating position, and a second pneumatic circuit (33) communicating with the lower chamber (31) so as to move the thrust element (20) to its raised rest position;
• and being characterized in that the first pneumatic circuit (32) is configured to supply the upper chamber (30) in a continuous manner and the second pneumatic circuit (33) is provided with a valve device (37) to supply the lower chamber (31) in a selective manner.