METHOD FOR PRODUCING AN ACOUSTIC PROTECTIVE SCREEN FOR A MOTOR VEHICLE ENGINE AND SCREEN OBTAINED BY SUCH A METHOD

摘要

A method for producing an acoustic protection screen for a motor vehicle engine, comprising providing a reflective metal thermal protection sheet having a plurality of micro perforations, providing a batt of fibres containing a thermosetting resin, superposing the metal thermal protection sheet and the batt in a first thermocompression mould, compressing the batt by binding the fibres together, in order to form a thermal insulation layer, and combining the metal thermal protection sheet with the layer using the thermosetting resin, placing the thermal protection shell against an upper wall of a second mould, the wall being provided with out-gassing vents, the sheet facing toward the wall, injecting into the second mould an air-porous polyurethane foam precursor mixture, the lower wall of the second mould being free of any fluid-tight coating, after the foam has expanded, demoulding the screen obtained, in which screen the foam forms a support overmoulding the layer.