Rotary buffing pad

Abstract

Provided is a flat-faced buffing pad that includes a plurality of apertures of variable size. The apertures are generally larger in the areas toward the center of the pad, while being generally smaller in the areas toward the periphery of the pad. Some embodiments further include apertures disposed along one or more concentric circular rings located along the front surface and generally symmetrical about the rotation axis. These configurations of apertures provide both superior cut performance and superior finish. Moreover, these configurations minimize several undesirable aspects in a polishing operation, such as slinging of the polishing compound, vibration, wobbling, and drag felt by the operator as the rotary pad slides across the surface to be polished.

1 . A rotary buffing pad comprising:
 a substrate comprising an open-celled polymeric foam that has a compression deflection value when compressed to 25 percent of original volume ranging from 2000 to 7000 Pascals and having a front surface, back surface, and a rotation axis perpendicular to the front and back surfaces, the substrate further comprising:   an inner region adjacent to and surrounding the rotation axis;
 an outer region surrounding the inner region; 
 a plurality of first apertures having a first average size located within the inner region and extending from the front surface toward the back surface; and 
 a plurality of second apertures having a second average size located within the outer region and extending from the front surface toward the back surface, wherein the first average size is larger than the second average size. 
   
     
     
         2 . A rotary buffing pad comprising:
 a substrate comprising an open-celled polymeric foam that has a compression deflection value when compressed to 25 percent of original volume ranging from 2000 to 7000 Pascals and having a front surface, back surface, and a rotation axis perpendicular to the front and back surfaces, the substrate further comprising:   an inner region adjacent to and surrounding the rotation axis;
 an outer region surrounding the inner region; 
 a plurality of first apertures having a first aperture density located within the inner region and extending from the front surface toward the back surface; and 
 a plurality of second apertures having a second aperture density located within the outer region and extending from the front surface toward the back surface, wherein the first aperture density is larger than the second aperture density. 
   
     
     
         3 . The buffing pad of  claim 2 , wherein the first aperture density ranges from 1.5 to 5.0 per square centimeter and the second aperture density ranges from 0.8 to 1.5 per square centimeter. 
     
     
         4 . The buffing pad of  claim 1 , wherein the plurality of second apertures include a first subset of second apertures arranged according to a series of replicated polygonal groupings that are spaced apart from each another. 
     
     
         5 . The buffing pad of  claim 4 , wherein the polygonal groupings are hexagonal groupings. 
     
     
         6 . The buffing pad of  claim 1 , wherein the plurality of first apertures have a first average depth and the plurality of second apertures have a second average depth that is less than the first average depth. 
     
     
         7 . The buffing pad of  claim 1 , wherein the plurality of first apertures have a first average diameter and the plurality of second apertures have a second average diameter that is less than the first average diameter. 
     
     
         8 . The buffing pad of  claim 1 , wherein the plurality of first apertures occupy a first average volume and the plurality of second apertures occupy a second average volume that is less than the first average volume. 
     
     
         9 . (canceled) 
     
     
         10 . The buffing pad of  claim 1 , wherein the inner region has a diameter ranging from 20 to 40 percent of the diameter of the substrate. 
     
     
         11 . The buffing pad of  claim 1 , wherein the inner region occupies an area ranging from 4 to 16 percent of the total area of the front surface. 
     
     
         12 . (canceled) 
     
     
         13 . The buffing pad of  claim 1 , further comprising a backing layer extending along at least a portion of the back surface and having a flexural modulus that is greater than that of the substrate. 
     
     
         14 . The buffing pad of  claim 13 , wherein the backing layer comprises a fibrous material to facilitate coupling to a power tool having a hook face attachment surface. 
     
     
         15 . The buffing pad of  claim 1 , wherein the plurality of first apertures include all of the apertures present within the inner region. 
     
     
         16 . The buffing pad of  claim 15 , wherein the plurality of second apertures include all of the apertures present within the outer region. 
     
     
         17 . The buffing pad of  claim 1 , wherein the outer region further comprises at least one annular region and wherein the plurality of second apertures further comprises a second subset of second apertures located in the at least one annular region, the second subset extending from the front surface toward the back surface and being disposed along at least one circular ring, each circular ring being coplanar with the front surface and generally symmetrical about the rotation axis. 
     
     
         18 . The buffing pad of  claim 17 , wherein the second subset of second apertures have a certain diameter and a certain spacing between neighboring apertures and the ratio between the certain diameter to the certain spacing is at least 0.2. 
     
     
         19 . The buffing pad of  claim 18 , wherein the ratio between the certain diameter to the certain spacing is at least 0.3. 
     
     
         20 . The buffing pad of  claim 19 , wherein the ratio between the certain diameter to the certain spacing is at least 0.35. 
     
     
         21 . The buffing pad of  claim 17 , further wherein the at least one annular region comprises two or more annular regions and the at least one circular ring comprises two or more circular rings that are located within the respective annular regions and concentric with each other. 
     
     
         22 . A rotary buffing pad comprising:
 a substrate comprising an open-celled polymeric foam that has a compression deflection value when compressed to 25 percent of original volume ranging from 2000 to 7000 Pascals and having a front surface, back surface, and a rotation axis perpendicular to the front and back surfaces, the substrate further comprising:   an inner region adjacent to and surrounding the rotation axis;
 an outer region surrounding the inner region; and 
 a plurality of apertures extending from the front surface toward the back surface, wherein the apertures have a distribution of sizes and the apertures having relatively large size are predominantly located in the inner region relative to the outer region.