Resonant Shaking

Abstract

A resonant shaker includes a support tray for supporting a target carrier. A sensor generates an electrical signal that is related to an acceleration of the support tray. A linear drive motor includes an armature that is coupled to the support tray. The linear drive motor provides an oscillating drive force to the support tray in response to a drive current applied to the linear drive motor. The resonant shaker also includes a controller. The controller receives the electrical signal from the sensor and a drive signal that is related to the drive current. The controller transmits a modified drive current to the linear drive motor in response to a predetermined phase relationship between the electrical signal and the drive signal.

1 . A method for use in connection with mixing of materials that have been loaded into a structure, the method comprising: 
 identifying a mechanical resonance frequency of the loaded structure, and automatically controlling a driving frequency of an actuator to cause the structure to shake at a shaking frequency that has a predefined relationship to the mechanical resonance frequency.    
   
   
       2 . The method of  claim 1  in which controlling the driving frequency comprises: 
 changing the driving frequency to maintain the predefined relationship in response to a change in the identified mechanical resonance frequency.    
   
   
       3 . The method of  claim 1  wherein the controlling comprises closed loop control.  
   
   
       4 . The method of  claim 1  wherein causing the structure to shake comprises causing the structure to shake substantially only along a particular axis.  
   
   
       5 . The method of  claim 1  wherein causing the structure to shake comprises causing the structure to shake vertically.  
   
   
       6 . The method of  claim 1  wherein causing the structure to shake comprises causing the structure to shake horizontally.  
   
   
       7 . The method of  claim 1  wherein the actuator comprises a linear actuator.  
   
   
       8 . The method of  claim 1  wherein the predefined relationship comprises having the shaking frequency be equal to the mechanical resonance frequency.  
   
   
       9 . The method of  claim 1  wherein the predefined relationship comprises having the shaking frequency be near to the mechanical resonance frequency.  
   
   
       10 . A method for use in connection with mixing of materials that have been loaded into a structure, the method comprising: 
 identifying a mechanical resonance frequency of the loaded structure, and automatically controlling via closed loop control a driving frequency of an actuator to cause the structure to shake vertically at a shaking frequency that has a predefined relationship to the mechanical resonance frequency.