Surface treatment apparatus with selective loading

Abstract

A surface treatment system using motors that drive abrasive pads to treat a surface has structure that applies a force on the abrasive pad that provides a non-uniform contact pressure between the abrasive pad and the treated surface. This allows the system to treat the surface more quickly. Several structures are disclosed for applying the necessary force to the abrasive pad. In preferred embodiments, the non-uniform contact pressure results from application of torque to a motor that drives the abrasive pad.

We claim: 
     
         1 . Apparatus for treating the surface of an article comprising a motor, a backup pad attached to the motor and driven by the motor, and means for applying a non-uniform contact pressure to the backup pad. 
     
     
         2 . Apparatus for treatment of a surface comprising a frame for holding an effector for treating said surface and a connector configured to attach said frame to an extension that controls contact between said effector and said surface, wherein said connector applies a force to said frame that results in application of a non-uniform contact pressure between said effector and said surface. 
     
     
         3 . Apparatus according to  claim 2  wherein said frame comprises a first bearing for mounting said effector to said frame for rotation about a first axis and said connector applies a torque to said frame about a second axis transverse to said first axis. 
     
     
         4 . Apparatus according to  claim 3  wherein said connector comprises a plate connected to said frame, a second bearing, and a post rotationally received in said second bearing for rotation about said second axis, wherein said post applies said torque to said frame. 
     
     
         5 . Apparatus according to  claim 4  further comprising said effector, wherein said effector comprises a motor and a backup pad, the motor rotating said backup pad about a motor axis, and wherein said torque is generated by a force applied to said post by said extension, said force being displaced from said motor axis in the direction of said first axis. 
     
     
         6 . Apparatus according to  claim 3  wherein said connector comprises at least one device connected to said frame for applying a linear force between said extension and said frame, said linear force generating said torque. 
     
     
         7 . Apparatus according to  claim 6  wherein said device comprises one or more pneumatic cylinders. 
     
     
         8 . Apparatus according to  claim 4  wherein said connector further comprises at least one device connected to said frame for applying a linear force between said extension and said frame, said linear force generating said torque. 
     
     
         9 . Apparatus according to  claim 3  wherein said connector comprises a rotary actuator. 
     
     
         10 . Apparatus according to  claim 4  wherein said connector further comprises a rotary actuator. 
     
     
         11 . Apparatus according to  claim 2  comprising said extension, an adaptor plate connected to said extension and having said frame attached thereto, and a second frame for holding a second effector for treating said surface and a second connector attaching said second frame to said adaptor plate, wherein said second connector applies a force to said second frame that results in application of a non-uniform contact pressure between said second effector and said surface. 
     
     
         12 . A method of treating a surface comprising moving an extension having mounted thereon an apparatus for treatment of said surface said apparatus comprising a frame holding an effector for treating said surface and a connector attaching said frame to said extension, operating said extension to provide contact between said effector and said surface, wherein said connector applies a force to said frame that results in application of a non-uniform contact pressure between said effector and said surface.