Box with lateral collapsible walls

Plastic moulded box with collapsible lateral walls, of the type in which the longitudinal walls (3, 4) are higher than half of the width of the transversal walls (5), wherein the two longitudinal walls (3, 4) are provided on top with shaped longitudinal bands (31, 41) with identical section and different dimensions, so that the internal side of the box-shaped band (41) of the second longitudinal wall (4) is exactly overlapped, receiving it completely, on the external side of the shaped band (31) of the first longitudinal wall (3) when both walls (3, 4) are collapsed in a sequence in horizontal idle position parallel to the bottom wall (2) of the box (1),

• said band (41 of the second longitudinal wall having a longitudinal rib (44) protruding from the upper horizontal border, able to engage into a longitudinal groove (31a) provided at the base of the shaped band (31) of the first wall (3),
• said first longitudinal wall (3) being laterally bordered by two stiffening edges (32) obtained on the vertical borders, but not for the entire height thereof,
• the lateral ends of the box-shaped band (31) of the first lateral wall being closed by corresponding partitions (33), occupying a more internal position than the adjacent stiffening edge (32),
• a transversal notch (34) being obtained in intermediate position between the stiffening edge (32) and the partition (33), said transversal notch (34) ending into a circular hole (35) on the surface of the first longitudinal wall (3),
• the second longitudinal wall (4) being provided with stiffening edges (42) on the vertical borders extending for the entire height of the vertical borders, said stiffening edges (42) being joined on top with very short edges (43) with identical height obtained at the two ends of the upper horizontal border of the shaped band (41) of the second longitudinal wall (40),
• the short edges (43) being joined on the opposite side, with the interposition of corresponding cylindrical pins (43a), with the ends of said longitudinal rib (44) that protrudes from the upper horizontal border of the shaped band (41) of the second longitudinal wall (4),
• so that, when the second longitudinal wall (4) is collapsed on the first longitudinal wall (3):
• the rib (44) is exactly engaged into the corresponding longitudinal grove (31a) provided at the base of the shaped band (31) of the first wall (3),
• the lateral short edges (43) are exactly engaged into the corresponding transversal notches (34) provided on the vertical borders of the first wall (3),
• the cylindrical pins (43a) are exactly engaged into the corresponding holes (35) obtained on the first longitudinal wall (3) in internal position in each notch (34), and
• the stiffening edge (42) of the second longitudinal wall (4) is brought in perfect alignment with the corresponding stiffening edge (32) of the first longitudinal wall (3).