Patent ID: 6399001
Filing Date: 2002-06-04
Classification: B27N

Abstract:
A method for the fabrication of a blank for a structural product, the method comprising the steps of:a) depositing material comprising particles of different sizes onto a first set of spaced substantially parallel rotating rollers; b) performing a segregation of the particles using the first set of rollers, whereby shorter particles, including short and shortest particles, fall through the spaces between the rollers, and longer particles pass over the rollers in a direction from an upstream end toward a downstream end of the first set of rollers and fall from the first set of rollers at the downstream end thereof; c) depositing the shorter particles falling from the first set of rollers onto a second set of spaced substantially parallel rotating rollers; d) performing a segregation of the shorter particles using the second set of rollers, whereby the shortest particles fall through the spaces between the rollers, and the short particles pass over the rollers in a direction from the upstream end of the second set of rollers toward a downstream end of the second set of rollers and fall from the second set of rollers at the downstream end thereof; e) depositing the longer particles falling from the first set of rollers onto an orienting mechanism, to thereby generally orient the longer particles in a common direction; and f) depositing, in a predetermined order, (1) the shortest particles falling from the second set of rollers, (2) the short particles falling from the second set of rollers and (3) the oriented longer particles from the orienting mechanism onto a moving support to thereby form superimposed layers of particles on the support, and wherein the outer surface layers are formed by the oriented longer particles, a central layer is formed by the shortest particles and intermediate layers are formed by the short particles.