Ultrasonic Processing Method and Apparatus with Multiple Frequency Transducers

Abstract

Ultrasonic processing apparatus and methods are disclosed, which includes multiple transducers of at least two different resonant frequencies supplying ultrasonic energy to a liquid filled tank containing components to be cleaned or processed ultrasonically. The transducers are arranged in equilateral triangular patterns along diagonal lines on a wall of the tank so that each transducer has an adjacent transducer of a different frequency. Alternatively, the apparatus includes one or more rod transducers having different resonant frequencies so that the apparatus provides a mixture of various frequencies of ultrasonic energy to the tank. Another aspect of the invention involves selecting transducers with different resonant frequencies that are outside an excluded subrange, and powering the transducers by a driving signal that sweeps through the resonant frequencies of the transducers and the excluded subrange.

1 . An ultrasonic processing apparatus comprising: 
 a tank operable for containing a fluid;    multiple ultrasonic transducers coupled to the tank and operable for supplying ultrasonic energy to the fluid in the tank, wherein a first group of the transducers has a first resonant frequency and a second group of the transducers has a second resonant frequency that is different from the first resonant frequency, and wherein the transducers are arranged in an equilateral triangular pattern along diagonal lines so that each transducer has at least two adjacent transducers and at least one adjacent transducer has a different resonant frequency; and    a generator means for supplying driving signals to the transducers.    
     
     
         2 . An apparatus as recited in  claim 1 , wherein the generator means includes a generator coupled to each group of transducers, wherein each generator supplies a driving signal at the resonant frequency of its associated group of transducers.  
     
     
         3 - 17 . (canceled)  
     
     
         18 . An apparatus as recited in  claim 1 , wherein the transducers are stacked transducers.  
     
     
         19 . An apparatus as recited in  claim 1 , wherein the transducers are rod transducers.  
     
     
         20 . An ultrasonic processing apparatus comprising: 
 a tank operable for containing a fluid;    multiple ultrasonic transducers coupled to the tank and operable for supplying ultrasonic energy to the fluid in the tank, wherein a first group of the transducers has resonant frequencies in a first resonant frequency range and a second group of the transducers has resonant frequencies in a second resonant frequency range that is different from the first resonant frequency range, and wherein the transducers are arranged in a triangular pattern along diagonal lines so that each transducer has at least two adjacent transducers and at least one adjacent transducer has a resonant frequency in a different resonant frequency range; and    a generator means for supplying driving signals to the transducers.    
     
     
         21 . An apparatus as recited in  claim 20 , wherein the generator means includes a generator coupled to each group of transducers, wherein each generator supplies a driving signal within the resonant frequency range of its associated group of transducers.  
     
     
         22 . An apparatus as recited in  claim 20 , wherein the generator means includes means for supplying driving signals that vary in frequency throughout the first and second resonant frequency ranges.  
     
     
         23 . An apparatus as recited in  claim 20 , wherein the transducers are stacked transducers.  
     
     
         24 . An apparatus as recited in  claim 20 , wherein the transducers are rod transducers.  
     
     
         25 . An ultrasonic processing method comprising the steps of: 
 providing multiple ultrasonic transducers operable for supplying ultrasonic energy, wherein a first group of the transducers has resonant frequencies in a first resonant frequency range and a second group of the transducers has resonant frequencies in a second resonant frequency range that is different from the first resonant frequency range, and wherein the transducers are arranged in a triangular pattern along diagonal lines so that each transducer has at least two adjacent transducers and at least one adjacent transducer has a resonant frequency in a different resonant frequency range; and    supplying driving signals to the ultrasonic transducers, wherein the driving signal varies in frequency throughout the first and second resonant frequency ranges.    
     
     
         26 . A method as recited in  claim 25 , wherein the step of supplying driving signals to the ultrasonic transducers includes providing a generator coupled to each group of transducers, wherein each generator supplies a driving signal within the resonant frequency range of its associated group of transducers.