Apparatus and method for high flow particle blasting without particle storage

Abstract

A particle blast apparatus transport is capable of generating granular sized particles and delivering them without substantial storage to a single hose feeder assembly. The apparatus is configured to be used with solid blocks of cryogenic material, such as carbon dioxide, and with individual pellets of such material.

We claim: 
     
         1 . An apparatus for metering discrete particles of carbon dioxide, the apparatus comprising:
 a. a storage bin configured to receive discrete particles therein, said storage bin comprising a first end;   b. an internal passageway;   c. a carrier interposed between said internal passageway and said first end of said storage bin, said carrier being moveable with respect to said storage bin, said carrier comprising a plurality of openings configured to pass said discrete particles therethrough from said storage bin to said internal passageway at a flow rate, at least one first opening of said plurality of openings having a size which is settable between and including a first size and a second size, the flow rate determined at least in part by the size of said at least one first opening of said plurality of openings; and   d. a plate disposed to move within said storage bin, said plate configured to urge the discrete particles disposed within said storage bin against said carrier.   
     
     
         2 . The apparatus of  claim 1 , further comprising
 a. said storage bin is also configured to receive a block of carbon dioxide;   b. said plate is also configured to urge said block against said carrier;   c. at least one second opening of said plurality of said openings comprising a working edge configured to shave particles from said block and to pass said shaved particles through said at least one second opening of said plurality of openings to said internal passageway.   
     
     
         3 . The apparatus of  claim 2 , wherein the at least one first opening of the plurality of openings comprises an insert moveable between and including a first position and a second position, the at least one first opening having said first size when said insert is disposed at said first position, and the at least one first opening having said second size when said insert is disposed at said second position. 
     
     
         4 . The apparatus of  claim 2 , wherein said insert comprises an over-center lever. 
     
     
         5 . The apparatus of  claim 2 , wherein at least one opening of said plurality of openings is disposed radially. 
     
     
         6 . The apparatus of  claim 5 , wherein said at least one radially disposed opening of said plurality of openings comprises said at least one second opening. 
     
     
         7 . The apparatus of  claim 2 , wherein at least one opening of said plurality of openings is disposed non-radially. 
     
     
         8 . The apparatus of  claim 2 , wherein said plate is resiliently biased toward said carrier. 
     
     
         9 . The apparatus of  claim 1 , wherein the at least one first opening of the plurality of openings comprises an insert moveable between and including a first position and a second position, the at least one first opening having said first size when said insert is disposed at said first position, and the at least one first opening having said second size when said insert is disposed at said second position. 
     
     
         10 . The apparatus of  claim 9 , wherein said insert comprises an over-center lever. 
     
     
         11 . The apparatus of  claim 9 , wherein at least one opening of said plurality of openings is disposed radially. 
     
     
         12 . The apparatus of  claim 11 , wherein said at least one radially disposed opening of said plurality of openings comprises said at least one second opening. 
     
     
         13 . The apparatus of  9 , wherein at least one opening of said plurality of openings is disposed non-radially. 
     
     
         14 . The apparatus of  claim 1 , wherein at least one opening of said plurality of openings is disposed radially. 
     
     
         15 . The apparatus of  claim 14 , wherein said at least one radially disposed opening of said plurality of openings comprises said at least one second opening. 
     
     
         16 . The apparatus of  1 , wherein at least one opening of said plurality of openings is disposed non-radially. 
     
     
         17 . The apparatus of  claim 1 , wherein said plate is resiliently biased toward said carrier. 
     
     
         18 . A method of metering a desired flowrate of discrete carbon dioxide particles, said method comprising:
 a. setting a respective size of at least one opening of a plurality of openings formed through a carrier, said at last one opening being settable at a plurality of sizes between and including a first size and a second size, said respective size being associated with said desired flow rate;   b. moving said carrier relative to said discrete carbon dioxide particles;   c. urging said discrete carbon dioxide particles against the carrier as the carrier moves; and   d. passing said plurality of carbon dioxide through said at least one opening into an internal passageway.   
     
     
         19 . The method of  claim 18 , wherein setting said respective size comprises operating an over-center lever. 
     
     
         20 . The method of  claim 19 , wherein operating said over-center lever comprises moving said over-center lever from an unlocked position to a locked position.