AN APPARATUS AND METHOD FOR FORMING AIR-LAID ABSORBENT CORES

THE PRESENT INVENTION RELATES TO AN APPARATUS FOR FORMING AIR-LAID ABSORBENT CORES (15, 16), COMPRISING A FIRST AND SECOND MAT-FORMING WHEEL (1, 2), EACH OF THE MAT-FORMING WHEELS HAVING A SERIES OF MOULDS (3, 4) ALONG THEIR PERIPHERAL SURFACE, AIR-LAYING MEANS (6, 10 AND 8, 12) FOR SUPPLYING AIR-ENTRAINED FIBROUS MATERIAL TO THE MOULDS ON EACH MAT-FORMING WHEEL, SUCTION MEANS (13, 14) MAINTAINING THE FORMED CORE ELEMENTS IN THE RESPECTIVE MOULDS DURING A PART OF THE PATH OF THE MOULDS ON THE RESPECTIVE MAT-FORMING WHEEL AND MEANS FOR TRANSFERRING A CORE ELEMENT (16) ON THE SECOND MAT-FORMING WHEEL ONTO A CORE ELEMENT (15) ON THE FIRST MAT-FORMING WHEEL WHILE THE LATTER CORE ELEMENT STILL IS MAINTAINED IN ITS MOULD, AT LEAST THE AIR-LAYING MEANS (8, 12) ASSOCIATED WITH THE SECOND MAT-FORMING WHEEL COMPRISES MEANS FOR SUPPLYING A MIXTURE OF AIR-ENTRAINED FIBROUS MATERIAL AND DISCRETE PARTICLES. ACCORDING TO THE INVENTION MEANS (5, 9 AND 7, 11) ARE ARRANGED FOR APPLYING A PROTECTIVE LAYER (22, 23) TO THE BOTTOM OF EACH MOULD (3, 4) OF AT LEAST THE SECOND MAT-FORMING WHEEL (2), WHICH PROTECTIVE LAYER (22, 23) HAS THE FUNCTION OF PROTECTING THE MOULD FROM DISCRETE PARTICLES DURING AIR-LAYING OF A MIXTURE OF AIR-ENTRAINED FIBROUS MATERIAL AND DISCRETE PARTICLES AND FOR PREVENTING DISCRETE PARTICLES FROM EXIT OUT OF THE SECOND CORE ELEMENT DURING AND AFTER TRANSFER, AND THE TWO MAT-FORMING WHEELS (1,2) FORMS SUCH A NIP BETWEEN EACH OTHER THAT THE SECOND CORE ELEMENT (16) WILL ABUT THE FIRST CORE ELEMENT (15) BEFORE TRANSFER. (FIG. 1)