Substrate grinding and polishing disk

Abstract

A grinding disk, surfacing platform, apparatus and method adaptable to a rotary concrete surfacing machine. A media disk is pivotally attached to a surfacing platform to maintain a substantially coplanar alignment of an abrasive or polishing media surface and the underlying substrate to be polished. The surfacing platform engages with rotating arms of the machine in operation and may be readily be detached by rotating in the opposite direction of operation.

What is claimed is: 
     
         1 . A grinding apparatus, comprising:
 a connecting shaft;   a media holder comprising an aperture defined through a top surface and a bottom surface of the media holder, the media holder pivotally coupled to the connecting shaft through the aperture for pivotal displacement about the connecting shaft; and   a media plate attached to the bottom surface of the media holder, the media plate comprising a lower surface comprising one of a grinding media, an abrasive media, or a polishing media.   
     
     
         2 . The apparatus of  claim 1 , further comprising:
 a magnet disposed in the media holder; and   a ferrous material attached to an upper surface of the media plate, wherein the media plate is removably attached to the media holder via magnetic attraction with the magnet.   
     
     
         3 . The apparatus of  claim 1 , further comprising:
 a magnet disposed in the media holder; and   the media plate is comprised of a ferrous material, and is removably attached to the media holder via magnetic attraction with the magnet.   
     
     
         4 . The apparatus of  claim 1 , wherein the media plate comprises a substantially circular disk. 
     
     
         5 . The apparatus of  claim 1 , wherein the media plate further comprises:
 a tapered edge defined around the periphery of a lower portion of the media plate.   
     
     
         6 . The apparatus of  claim 4 , wherein the media plate further comprises:
 a plurality of radially extending channels defined in a bottom surface of the disk.   
     
     
         7 . The apparatus of  claim 1 , further comprising:
 a hemispherical nut operatively coupled to the connecting shaft, the hemispherical nut comprising an upper rounded surface; and   the media holder is pivotally disposed on the upper rounded surface of the hemispherical nut.   
     
     
         8 . The apparatus of  claim 7 , the media holder further comprising:
 an attachment adapter attached to the top surface of the media holder, a rounded depression defined in a lower surface of the attachment adapter, the depression adapted to pivotally receive the upper rounded surface of the hemispherical nut and the connecting shaft.   
     
     
         9 . The apparatus of  claim 8 , the attachment adapter further comprising:
 a channel defined in an upper surface of the attachment adapter surrounding the connecting shaft; and   a flex ring received in the channel and disposed about the connecting shaft.   
     
     
         10 . The apparatus of  claim 1 , the media holder further comprising:
 a slot defined in an outer face of the medial holder, the slot providing an opening between the bottom surface of the media holder and a top surface of the media plate.   
     
     
         11 . A surface grinding apparatus, comprising:
 a platform plate comprising a top surface and a bottom surface;   a plurality of brackets attached to the top surface of the platform plate, the brackets defining an opening between the bracket and the top surface of the platform plate; and   a plurality of grinding assemblies extending from the bottom surface of the platform plate, disposed in spaced apart relation around a periphery of the platform plate, the grinding assemblies comprising a media holder pivotally coupled to the platform via a coupling shaft.   
     
     
         12 . The surface grinding apparatus of  claim 11 , further comprising:
 a media plate attached to a bottom surface of the media holder, the media plate comprising a lower surface of one of a grinding media, an abrasive media, or a polishing media.   
     
     
         13 . The surface grinding apparatus of  claim 12 , the grinding assembly further comprising:
 a slot defined in an outer face of the medial holder, the slot providing an opening between the bottom surface of the media holder and a top surface of the media plate.   
     
     
         14 . The surface grinding apparatus of  claim 11 , the media holder further comprising:
 an attachment adapter attached to a top surface of the media holder, a rounded depression defined in a lower surface of the attachment adapter, the depression adapted to pivotally receive an upper rounded surface of a hemispherical nut, wherein the hemispherical nut is operatively coupled to the connecting shaft.   
     
     
         15 . The surface grinding apparatus of  claim 14 , further comprising:
 a channel defined in an upper surface of the attachment adapter; and   an flex ring received in the channel and disposed between the attachment adapter and the platform plate.   
     
     
         16 . The surface grinding apparatus of  claim 15 , wherein the flex ring is comprised of a resilient material. 
     
     
         17 . The surface grinding apparatus of  claim 11 , further comprising:
 a rotary power trowel, comprising a plurality of rotating arms, wherein the arms are received in the bracket openings to secure the platform plate with the power trowel with an operating rotation of the power trowel.   
     
     
         18 . The surface grinding apparatus of  claim 17 , wherein the platform plate is detachable from the power trowel with a counter rotation of the platform plate. 
     
     
         19 . A method for polishing a substrate surface, comprising:
 providing a powered rotary surfacing machine, comprising a plurality of surfacing arms;   providing a platform plate comprising a top surface and a bottom surface;
 a plurality of brackets attached to the top surface of the platform plate, the brackets defining an opening between the bracket and the top surface of the platform plate; 
 a plurality of grinding assemblies extending from the bottom surface of the platform plate, disposed in spaced apart relation around a periphery of the platform plate, the grinding assemblies comprising a media holder pivotally coupled to the platform via a coupling shaft; and 
   attaching the platform plate to engage the brackets with the surfacing arms to secure the platform plate to the power trowel.   
     
     
         20 . The method of  claim 19 , further comprising:
 attaching a media plate to a bottom surface of the media holder, the media plate comprising a lower surface of at least one of a grinding media, an abrasive media, or a polishing media.