Apparatus and Method for Refinishing a Surface In-Situ

Abstract

A rotary grinding system includes a support frame and a grinding assembly coupled to the support frame for longitudinal movement, with respect to a workpiece attached to the support frame. A radial arm is suspended below the grinding assembly and rotated in a plane parallel to the workpiece. A grinding wheel traverses the radial arm, thereby working a circular, annular or sector portion of the workpiece. The height, and therefore the depth of cut, of the grinding wheel may be precisely adjusted via a single point adjustment screw or the like. Optionally, the grinding system may be controlled by a computer numeric controller (CNC) to automatically refinish programmed portions or all of the workpiece. Eccentric pins extending from the support frame and into the workpiece may be used to adjust the lateral position of the support frame, relative to the workpiece. Support members may be used to offload the weight of at least a portion of the grinding assembly, thereby relieving bearings of this weight, such as during shipment or storage of the system.

1 . A rotary grinder system for coupling with a workpiece, comprising:
 a support frame having an engagement region configured to be coupled to the workpiece;   a grinder assembly coupled to the support frame, the grinder assembly having an axial arm and a radial arm coupled to the axial arm in a substantially orthogonal orientation, the radial arm coupled to the axial arm such that the radial arm rotates about an axis of the axial arm;   a grinder wheel rotatably coupled to the radial arm of the grinder assembly via a grinder wheel driver and translatable along the radial arm; and   a single point axial positioner configured to translationally drive, with respect to the support frame, the radial arm of the grinder assembly along the axis of the axial arm.   
     
     
         2 . A rotary grinding system according to  claim 1 , wherein the single point axial positioner comprises a ball screw system. 
     
     
         3 . A rotary grinding system according to  claim 2 , wherein the single point axial positioner comprises a mechanical slide. 
     
     
         4 . A rotary grinding system according to  claim 1 , wherein the single point axial positioner is configured to drive the radial arm though translation of the axial arm. 
     
     
         5 . A rotary grinding system according to  claim 1 , wherein the single point axial positioner is configured to drive the radial arm through rotation of the axial arm. 
     
     
         6 . A rotary grinding system according to  claim 1 , wherein the single point axial positioner is configured to drive the radial arm through extension of the axial arm. 
     
     
         7 . A rotary grinding system according to  claim 1 , wherein the grinder assembly is coupled to the support frame via at least one slide assembly connected to the axial arm of the grinding assembly and to the support frame. 
     
     
         8 . A rotary grinding system according to  claim 1 , wherein the axial arm comprises a telescoping arm configured to change length upon application of force from the single point axial positioner. 
     
     
         9 . A rotary grinding system according to  claim 1 , wherein the grinder wheel is coupled to a mechanical slide on the radial arm and configured to translate along an axis of the radial arm, wherein translation of the mechanical slide along the radial arm displaces the grinder wheel. 
     
     
         10 . A rotary grinding system according to  claim 1 , wherein the radial arm includes a telescoping arm, the grinder wheel coupled thereto. 
     
     
         11 . A rotary grinding system according to  claim 1 , further comprising a counterweight coupled to the grinder assembly and to the support frame and configured to urge the grinder assembly in a direction away from the workpiece, along the axis of the axial arm. 
     
     
         12 . A rotary grinding system according to  claim 11 , wherein the counterweight comprises at least one of a hydraulic device, a spring and a mass-based counterweight. 
     
     
         13 . A rotary grinding system according to  claim 1 , further comprising a counterweight movably coupled to the radial arm and configured to move along the radial arm a distance proportional to, and in a direction opposite, the grinder wheel. 
     
     
         14 . A rotary grinding system according to  claim 13 , wherein the counterweight includes at least one of a chain drive, a screw drive and a dual rack with an interconnecting gear drive. 
     
     
         15 . A rotary grinding system according to  claim 1 , further comprising a micrometer adjustable dressing tool configured to dress the grinder wheel. 
     
     
         16 . A rotary grinding system according to  claim 1 , wherein the support frame comprises an upper frame coupled to a lower frame. 
     
     
         17 . A rotary grinding system according to  claim 1 , further comprising a plurality of eccentric pins, each eccentric pin extending through a respective hole defined by the support frame and into the workpiece, such that rotation of at least one of the eccentric pins laterally displaces the support frame, relative to the workpiece. 
     
     
         18 . A rotary grinding system according to  claim 1 , further comprising at least one support member connected between the support frame and the grinder assembly and configured to selectively support weight of at least a portion of the grinder assembly. 
     
     
         19 . A rotary grinding system according to  claim 1 , further comprising a computer numerical control electrically connected to a first actuator configured to adjust the single point axial positioner and to a second actuator configured to translate the grinder wheel driver along the radial arm, each of the actuators including encoders for measuring magnitude of the respective adjustment and translation. 
     
     
         20 . A rotary grinding system according to  claim 1 , wherein the grinder assembly includes at least one slip ring configured to transmit electrical signals to the radial arm during rotation of the radial arm. 
     
     
         21 . A rotary grinding system according to  claim 1 , wherein the grinder assembly includes at least one hydraulic rotary union configured to transmit hydraulic fluid to the radial arm during rotation of the radial arm. 
     
     
         22 . A rotary grinding system according to  claim 1 , wherein the grinder assembly includes at least one mechanical stop on at least one of the axial arm and the radial arm. 
     
     
         23 . A rotary grinding system according to  claim 1 , wherein the grinder wheel is retractable translationally beyond a zero point on the radial arm, so as to expose a diameter of the workpiece. 
     
     
         24 . A rotary grinding system according to  claim 1 , further comprising an adapter plate, wherein the support frame is configured to be coupled to the workpiece via the adapter plate.