Patent ID: 7071706

Claim:
a process for the non-destructive net weighing of capsules, comprising: (a) generating a variable frequency electromagnetic radiation in a microwave generator under the control of a processor and supplying said radiation to a probe applicator in the form of a resonator, the microwave signal leaving the applicator being supplied to a detector diode from whose signals b(0) and f(0) are determined by the computer as primary measurement values by means of an analogue-to-digital converter wherein b(0) is the half-power width at the resonant frequency f(0) of the applicator; (b) determining the measuring signals according to the equation: F=f ( L )− f (0) or B=b (0)− b ( L ) wherein F and B are the microwave measuring signals of the detuning and propagation of the resonance, with f(L) and b(L) being equal to constant material-dependent reference values; (c) determining the gross weight signal by weighing the gravimetric gross and applying it in the following equation: C=mT+m N , wherein the magnitude m T represents the mass of the empty packaging and the magnitude m N represents the net mass to be determined; and (d) determining the net mass m N according to the following equation m N =αF+βB+γC+δ wherein the measuring signals F, B, and C are determined above and the coefficients α, β, γ and δ having been determined by calibration of the measuring system by linear regression from a measuring series with reference samples of known net weight.