Housing ventilation system, housing and housing portion, use of said system, and mold for manufacturing

A ventilation system on a housing or a housing portion that houses a contents (39) and has ventilation grids (3;

• 33, 35) for said contents, said grids being formed from segments of material leaving a gap (7) between them, characterized in that
• these segments of material (5a, 5b, 5c) are arranged at at least two levels (9a, 9b) offset depthwise in the general direction (11) of entry of a gaseous fluid into the housing or the housing portion through the grid in question, in order to constitute, by grid, a multiple-grid system, the grids being offset depthwise with respect to one another,
• with a distance between two adjacent segments of material (5a, 5b) of less than about 1 mm, for an anti-intrusion effect, and
• further comprising at least two housing portions (31, 32) cooperating with one another to form a closed complete housing, at least two grids (33, 35), each consisting of a said multiple-grid system and belonging to the two housing portions, being arranged at least partly approximately face to face, or in a relative situation in the immediate vicinity of such a face-to-face arrangement.

A ventilation system on a housing or a housing portion that houses a contents (39) and has ventilation grids (3;

• 33, 35) for said contents, said grids being formed from segments of material leaving a gap (7) between them, characterized in that
• these segments of material (5a, 5b, 5c) are arranged at at least two levels (9a, 9b) offset depthwise in the general direction (11) of entry of a gaseous fluid into the housing or the housing portion through the grid in question, in order to constitute, by grid, a multiple-grid system, the grids being offset depthwise with respect to one another,
• with a distance between two adjacent segments of material (5a, 5b) of less than about 1 mm, for an anti-intrusion effect, characterized in that:
• it comprises first and second offset multiple-grid systems (33, 35) formed in two opposed walls of this housing;
• the contents of the housing comprises electronic components (39) placed on at least one board (37) installed in the housing, approximately parallel to the levels of the grid systems;
• the board(s) fitted with electronic components is(are) drilled with holes (41, 43) for air to flow from one side of the board to the other;
• and
• at least one of these holes and at least one portion of the first and second multiple-grid systems are approximately aligned for an approximately rectilinear flow of air inside the housing, between the first and second grid systems (33, 35).

A mold for manufacturing at least one housing portion to house a contents (39) and having ventilation grids (3;

• 33, 35) for said contents, said grids being formed from segments of material leaving a gap (7) between them, characterized in that
• these segments of material (5a, 5b, 5c) are arranged at at least two levels (9a, 9b) offset depthwise in the general direction (11) of entry of a gaseous fluid into the housing or the housing portion through the grid in question, in order to constitute, by grid, a multiple-grid system, the grids being offset depthwise with respect to one another,
• between the levels (9a, 9b), the segments of material are offset transversely to the depth so that they do not overlap between two adjacent levels,
• at the various levels, the segments of material (5a, 5b, 5c) forming the multiple-grid system comprise bars approximately parallel to one another, the mold comprising:
• first and second blocks (21, 22) placed approximately face to face and each having a molding face for defining at least one molding cavity (23) for molding said housing portion, the molding face of each block having a crenelation formed from alternating projections and recesses (27, 29) offset from one face to the other so that the projections on one face penetrate the recesses in the other face, in the molding position of the two blocks of the mold.

A ventilation system, comprising:

• a ventilation housing having an upper exterior surface;
• and
• ventilation grids located on the upper exterior surface,
• the grids being comprised of plural longitudinal segments spaced apart by a gap between adjacent segments,
• the segments arranged in at least two levels offset depthwise in a general direction orthogonal to the upper exterior surface and constituting at least a first grid layer offset depthwise with respect to a second grid layer.