公开(公告)号：CS8805504A3

公开(公告)日：1992-11-18

申请号：CS550488

申请日：1988-08-08

Applicant: SATRONIC AG

Inventor： KONRAD MANFRED

IPC: B05B17/06 ,  B06B1/02 ,  H03L7/00 ,  B06B1/06 ,  H03L7/097

CPC classification number: B05B17/0669 ,  B05B17/0607 ,  B06B1/0253 ,  B06B2201/77

公开(公告)号：CS550488A3

公开(公告)日：1992-11-18

申请号：CS550488

申请日：1988-08-08

Applicant: SATRONIC AG

Inventor： KONRAD MANFRED

IPC: B05B17/06 ,  B06B1/02 ,  H03L7/00 ,  H03L7/097 ,  B06B1/06

Abstract: A method and a circuit for exciting an ultrasonic generator comprises a control loop which includes the ultrasonic generator itself and a voltage-controlled oscillator. The control loop keeps the active power consumption to a desired value, which is compared in a comparator with the instantaneous active power consumption. One output of a further rectangular oscillator is connected to the control input of the voltage-controlled oscillator. The rectangular oscillator is put into operation if in the control loop there are no control oscillations or only those which are smaller than a predetermined threshold. The output of the rectangular oscillator is connected across one diode to the control input of the voltage-controlled oscillator and across another diode to the controlled input of comparator. The additional signal is applied to the voltage-controlled oscillator, apart from the control signal of the control loop. The cycle of the additional signal is longer than the change time constant at the control input of the voltage-controlled oscillator and the additional signal swing is selected in such a way that the frequency of oscillator passes through a predetermined frequency range.