Mechanical system comprising a wear part and a support, and a bucket comprising at least one such mechanical system

Mechanical system (1) comprising a wear part (10) and a support (20) that belong to a heavy-construction machine bucket (G), the support (20) comprising:

• a base (22),
• a nose (30) that extends from the base (22) along a principal axis (X30), between a proximal end (31) close to the base (22) and a distal end (33) opposite to the base (22), the nose having a set of cross-sections (50, 70, 90), in planes perpendicular to the principal axis (X30), that change in a proximal direction (D31) while delimiting increasing or constant areas, in particular not delimiting any decreasing area, apart from the presence of a housing for receiving a connection device in the nose (30), and
• on each side of the base (22), a housing (24) receiving a lug (14) belonging to the wear part (10), the housing (24) being provided in the base (22) in line with the nose (30), with an open side in a distal direction (D33) as well as three closed sides,
• the mechanical system (1) being characterised in that the nose (30) comprises:
• a first zone (40) that is situated in the vicinity of the proximal end (31) of the nose (30) and comprises at least six flat faces (41-48) opposite in pairs (41, 45;
• 42, 46;
• 43, 47;
• 44, 48) delimiting cross-sections of a first type (50), and
• a second zone (80) that is situated in the vicinity of the distal end (33) of the nose (30) and comprises at least six flat faces (81-88) opposite in pairs (81, 85;
• 82, 86;
• 83, 87;
• 84, 88) delimiting cross-sections of a second type (90), each flat face (81-88) of the second zone (80) being less inclined, with respect to the principal axis (X30), than the flat face (41-48) of the first zone (40) that is situated in line with it along the proximal direction (D31).