Abstract: A device for thermal regeneration of particle filters is provided for use with a diesel engine exhaust system with a particle filter. The device includes a burner for heating the particle filter during regeneration of the particle filter. A combustion air supply is provided connected to the burner for supplying combustion air. A fuel pump arrangement is provided preferably including plural pumps which are individually actuatable to deliver fuel dependent on the speed and load condition of the diesel engine.

Abstract: A method for driving an ultrasonic transducer, intended for use in atomization of liquids, at one of its selected resonance frequencies, by tuning out the capacitance of the ultrasonic transducer by means of an inductor, by sensing the transducer current, by comparing the phases of the transducer driving voltage and the transducer current and by controlling a voltage controlled oscillator for driving the ultrasonic transducer, by means of a phase error signal such that the ultrasonic transducer is driven with a frequency at which the transducer driving voltage and the transducer current are in phase, whereby the transducer driving circuit is locked to a natural resonance frequency of the ultrasonic transducer.

Abstract: A method for driving an ultrasonic transducer, intended for use in atomization of liquids, at one of its selected resonance frequencies, by tuning out the capacitance of the ultrasonic transducer by means of an inductor, by sensing the transducer current, by comparing the phases of the transducer driving voltage and the transducer current and by controlling a voltage controlled oscillator for driving the ultrasonic transducer, by means of a phase error signal such that the ultrasonic transducer is driven with a frequency at which the transducer driving voltage and the transducer current are in phase, whereby the transducer driving circuit is locked to a natural resonance frequency of the ultrasonic transducer.