An apparatus (20) for the continuous production of a mattress (14) of agglomerated mineral fibres is described, comprising a mineral fibre receiving or forming chamber (2), an accumulator conveyer (3) arranged below the receiving or forming chamber (2) and comprising adjacent drums (4) provided with perforated or gas-permeable circumferential surfaces (5) for receiving and accumulating the fibres to form a mattress (14) comprising mineral fibres between the drums (4), a gas extraction device (6) in fluid communication with the perforated or gas-permeable circumferential surfaces (5) of the drums (4) and a lower space between the drums (4) for unloading the mattress (14) of mineral fibres formed between the drums (4), the apparatus (20) being characterized in that said drums (4) comprise each a first half-drum (4a) and a second half-drum (4b) telescopically connected with each other and which are movable along the axis of rotation (X) between a first stroke-end position in which the first half-drum (4a) and the second half-drum (4b) are juxtaposed or in contact with each other, and a second stroke-end position in which the first half-drum (4a) and the second half-drum (4b) are spaced apart from each other at a predetermined maximum distance along the direction of the axis (X) of rotation of the drums (4), a gas-permeable or perforated circumferential band (22) being furthermore provided, which overlaps at least one of said first half-drum (4a) and said second half-drum (4b) at opposite end portions of said half-drums (4a,4b).

An apparatus (20) for the continuous production of a mattress (14) of agglomerated mineral fibres is described, comprising a mineral fibre receiving or forming chamber (2), an accumulator conveyer (3) arranged below the receiving or forming chamber (2) and comprising adjacent drums (4) provided with perforated or gas-permeable circumferential surfaces (5) for receiving and accumulating the fibres to form a mattress (14) comprising mineral fibres between the drums (4), a gas extraction device (6) in fluid communication with the perforated or gas-permeable circumferential surfaces (5) of the drums (4) and a lower space between the drums (4) for unloading the mattress (14) of mineral fibres formed between the drums (4), the apparatus (20) being characterized in that said drums (4) comprise each a first half-drum (4a) and a second half-drum (4b) telescopically connected with each other and which are movable along the axis of rotation (X) between a first stroke-end position in which the first half-drum (4a) and the second half-drum (4b) are juxtaposed or in contact with each other, and a second stroke-end position in which the first half-drum (4a) and the second half-drum (4b) are spaced apart from each other at a predetermined maximum distance along the direction of the axis (X) of rotation of the drums (4), a gas-permeable or perforated circumferential band (22) being furthermore provided, which overlaps at least one of said first half-drum (4a) and said second half-drum (4b) at opposite end portions of said half-drums (4a,4b).