Patent GB-1396786-A (GB)
Title: Method and apparatus for manufacturing hard boards of mineral fibres
IPC: B28B1/52
Filed: 1972-05-15
Abstract: 1396786 Laminated boards VYZKUMNY USTAV MECHANIZACE AUTOMATIZACE A TECHNOLOGIE VYROBY STAVEBNICH DILCU 15 May 1972 [28 May 1971] 22764/72 Heading B5N [Also in Division D1] In a method of producing laminated hard boards from mineral fibres, e.g. slag or basalt fibres, a continuous sheet, composed of fibres which have been sprayed with a synthetic resin is cut into lengths, the thickness uniformity of each length is checked, and, if correct, both surfaces of the length are sprayed to saturation with a synthetic resin, e.g. a phenol-formaldehyde resin, a first length is positioned on a first support element covered with a first separating sheet, e.g. a sulphate paper, one or more additional lengths are positioned on said first length and the upper surface of the upper length is covered with a second separating sheet on which a second support element is positioned and the resultant sandwich pressed and heated. In a modification of the method, one or more reinforcements are included between or as facings for the lengths. An apparatus for effecting the method comprises means, e.g. transverse saw 21 for cutting the sheet into lengths, a unit, e.g. radiometric checking unit 2 for checking the thickness of each length, means positioned at said unit for the removal of lengths of incorrect thickness, a saturating unit 4 for saturating each face of each length of correct thickness, a unit for positioning each length 18 on a first support element 23 covered with a first separating sheet, means for applying a second separating sheet and a second support element and means, e.g. press 10 for applying heat and pressure. In the embodiment described, the starting material is fibred by a rotary head and sprayed with a synthetic resin in settling chamber 1, the fibres being deposed in the form of an endless sheet on a grid forming the floor of the chamber. The lengths of correct thickness are fed from checking unit 2 on to a conveyer 3 and into the saturation unit 4 ; the rejected lengths being fed by conveyers 3,17 and 3<SP>1</SP> to packing equipment 19. The position ing unit 5 comprises a carrier 26 the upper part of which is provided with a driven conveyer belt 27 inclined downwards in the direction of advance of the severed lengths 18 at 3 to 15 degrees, a support sheet 23, e.g. a metal sheet being located below the lower span of the belt conveyer 27, the carrier 26 being moveable on wheels along guides so that it can lay a severed length 18 on to the support sheet, the positioning unit 5 transferring each severed length 18 into a space between the supply tank 6 for separating foils and pressing rollers 8 and putting the length on a separating foil spread on the support sheet, the severed length being covered with another separating foil and a second support sheet 23 brought over by arm 7 to form a sandwich which is passed between rollers 8 and into stacker unit 9, a plurality of sandwiches being transferred when the stacker unit 9 is full into the multidaylight press 10. The press unloader 11 transfers the pressed assemblies from the press. Means are provided for removing the separating sheets and support elements and for trimming the boards.