Abstract: A sorting machine is disclosed for sorting objects by examining light from the objects in at least two different parts of the spectrum. The objects to be sorted are fed to a viewing zone where they are illuminated in at least two different parts of the spectrum. The objects passing through the viewing zone are viewed against at least one background which is illuminated by at least first and second lighting units which are separate from the lighting employed to illuminate the viewing zone, the first and second lighting units being respectively arranged to cause the respective background to emit light in the at least two different parts of the spectrum. A discriminator is employed for determining whether objects which have been so viewed are desired, and there is an object separator controlled by the discriminator, for effecting relative separation between desired and undesired objects.

Abstract: A strip of coherent packets of compacted batches of ground coffee between two overlapping webs of water-permeable material is formed along the upper reach of an endless conveyor with plates having supporting surfaces facing upwardly during travel along the upper reach and provided with recesses which communicate with a suction generating device. The first web is deposited onto the supporting surfaces of successive plates at a first station, followed by deformation of the web at a second station to form therein pockets which extend into the respective recesses and receive batches containing metered quantities of ground coffee at a third station. The batches are compacted in two stages to form cakes from which loose particles are sucked up by a nozzle before the second web is placed over the first web and the cakes.