Patent ID: 7868260

Claim:
Apparatus for dispensing particles, comprising: a particle retainer for retaining a supply of particles to be dispensed; a particle release actuator for causing, in response to an actuation signal, some of said supply of particles to be dispensed from said particle retainer; a weight measuring device for measuring an apparent weight of particles dispensed from said particle retainer and for outputting a signal representing the measured apparent weight of the particles dispensed; a processor operatively connected to said particle release actuator and arranged to provide said actuation signal thereto, said processor also being operatively connected to said weight measuring device and being arranged to receive said measured apparent weight signal therefrom; wherein said processor is arranged to vary the number of particles to be dispensed by varying a characteristic of the actuation signal it provides to said particle release actuator; wherein said particle release actuator is arranged, upon receiving said actuation signal, to transmit a discrete impulse of force to said particle retainer; and wherein the energy of said discrete impulse of force corresponds to a characteristic of said actuation signal provided to said particle release actuator, whereby the number of particles dispensed from said particle retainer is related to the energy of said discrete impulse of force.