Device for automatic closing of a door

An automatic closing system for automatically closing a leaf (5) with respect to a fixed structure (6), said system comprising at least one hidden hinge (4) for articulating said leaf (5) with respect to said fixed structure (6), said hidden hinge (4) comprising:

• a first body (8), with a corresponding first containment seat (14), adapted to be inserted into a corresponding first cavity (7) obtained in said leaf (5);
• a second body (10), with a second containment seat (15), adapted to be recessed in a corresponding second cavity obtained in said fixed structure (6);
• rocker-shaped arms (48, 60) associated with said first and said second bodies (8, 10) so as to allow a rotation of the leaf (5) with respect to said fixed structure (6);
• and
• a device (2, 2′) for automatic closing of a door, constrained to a base (13) of said first body (8) of said hinge (4) and adapted to be inserted, together with said first body (8), into said first cavity (7) obtained in said leaf (5), said device comprising:
• a translating element (34) adapted to be engaged with an articulation arm (48) of said hinge (4);
• an elastic member (42) interposed between a first element (44) adapted to translate with said translating element (34) and a second element (47) associated with said body (8) of said hinge (4) to which said device (2, 2′) is intended to be constrained, said elastic member (42) being configured to be loaded during an opening rotation of said leaf (5) associated with said hinge (4) and to return mechanical energy stored in said opening rotation to said translating element (34) in order to cause the automatic closing of said leaf (5) associated with said hinge (4);
• a system (50, 51, 52, 53, 55, 57) adapted to vary a preloading of said elastic member (42), and therefore an automatic closing speed of said leaf (5), said system (50, 51, 52, 53, 55, 57) being configured to modify a distance between said first (44) and said second (47) elements between which said elastic member (42) is interposed,
• wherein said system (50, 51, 52, 53, 55, 57) adapted to vary the preloading of said elastic member (42):
• is configured to be controlled from a base (75) of said body (8) of said hinge (4), which is visible also once said device (2, 2′) has been inserted into said cavity (7) obtained in said leaf (5), and
• comprises a system adapted to modify, when adiusting said device (2, 2′) for automatic closing of a door, a distance between said second element (47) and a lower base of said body (8) of said hinge (4), to which said device (2, 2′) is adapted to be constrained.