Patent ID: 7340967

Claim:
Device for measuring a mass flow rate of a flow of particulate material which flows in a predetermined direction, the device being situated in the flow of particulate material, the device comprising: a weighing cell that includes a tubular wall defined between an internal face and an external face, the tubular wall of the weighing cell being at least locally transparent in order to allow observation, from outside the weighing cell, of the particulate material which flows against an internal face of the tubular wall, the weighing cell having a volume of predetermined value, a cross section of predetermined value, and a weight of predetermined value, the weighing cell being disposed to be passed through by the flow of particulate material; a first apparatus which, at least during a first predetermined time interval, weighs a total weight of the weighing cell and a quantity of particulate material contained in the weighing cell, and produces a first signal representing at least the value of the total weight of the weighing cell and the quantity of particulate material contained in the weighing cell, a second apparatus which, at least during the first predetermined time interval, measures the speed of flow of the particulate material through the weighing cell and produces a second signal representing the speed of flow of the particulate material contained through the weighing cell, wherein the second apparatus includes a fourth apparatus to capture and register, through the tubular wall, during at least the first predetermined time interval, two successive images of the particulate material in contact with the internal face of the tubular wall of the weighing cell, the two successive images constituting a group of a first image and a second image; and a third apparatus which uses the first signal, the second signal, the predetermined value of the volume of the weighing cell, the predetermined value of the cross section of the weighing cell and the predetermined value of the weight of the weighing cell to calculate the bulk density of the particulate material, calculate the mass flow rate of particulate material which flows through the weighing cell during the first predetermined time interval, and produce a third signal representing the mass flow rate of particulate material which flows through the weighing cell during the first predetermined time interval.