A cutting head assembly

Abstract

A cutting head assembly for excavating rock fragments from a mine wall is disclosed. In an embodiment, the cutting head assembly comprises a primary breakage mechanism actuable to apply, to the mine wall, a breakage force for breaking rock fragments from the mine wall. A surface of the cutting head assembly catches the rock fragments broken from the mine wall and has one or more ports associated therewith. A secondary breakage mechanism is operatively associated with the surface and actuable to apply a force for reducing the size of at least some of the rock fragments caught by the surface so as to allow at least the reduced size rock fragments to pass through a respective port for transportation to downstream processing.

1 . A cutting head assembly for excavating rock fragments from a mine wall, the cutting head assembly comprising:
 a primary breakage mechanism actuable to apply, to the mine wall, a breakage force for breaking rock fragments from the mine wall;   a surface for catching the rock fragments broken from the mine wall, the surface having one or more ports associated therewith; and a   secondary breakage mechanism operatively associated with the surface, the secondary breakage mechanism actuable to apply a force for reducing the size of at least some of the rock fragments caught by the surface so as to allow at least the reduced size rock fragments to pass through a respective port for transportation to downstream processing.   
     
     
         2 . The cutting head assembly of  claim 1 , wherein the primary breakage mechanism comprises one or more primary cutters for breaking rock fragments from the mine wall. 
     
     
         3 . (canceled) 
     
     
         4 . The cutting head assembly of  claim 1 , wherein the breakage force is a percussive force applied by actuation of the primary breakage mechanism. 
     
     
         5 . The cutting head assembly of  claim 4 , wherein the percussive force of the primary breakage mechanism provides between 50 to 1000 J of impact energy at 20 to 400 Hz to break rock fragments from the mine wall. 
     
     
         6 . (canceled) 
     
     
         7 . The cutting head assembly of  claim 1 , wherein the secondary breakage mechanism comprises one or more secondary cutters. 
     
     
         8 . The cutting head assembly of  claim 5 , wherein the one or more secondary cutters comprises one or more blades reducing the size of at least some of the rock fragments caught by the surface and wherein the one or more blades are proximally associated with the one or more ports. 
     
     
         9 - 10 . (canceled) 
     
     
         11 . The cutting head assembly of  claim 7 , wherein the one or more secondary cutters of the secondary breakage mechanism is are associated with at least one of the primary cutters of the primary breakage mechanism. 
     
     
         12 . The cutting head assembly of  claim 1 , wherein the primary breakage mechanism is actuated by a primary actuator and the secondary breakage mechanism is actuated by a secondary actuator. 
     
     
         13 . The cutting head assembly of  claim 12 , wherein the primary and secondary actuators are independently operable. 
     
     
         14 . The cutting head assembly of  claim 12 , wherein the secondary actuator actuates the secondary breakage mechanism subsequent to the primary actuator actuating the primary breakage mechanism. 
     
     
         15 . The cutting head assembly of  claim 1 , wherein the assembly further comprises a fluid passageway concealed within a housing and a drive gear mounted on a top of the housing, the fluid passageway extending between the one or more ports and an outlet. 
     
     
         16 . The cutting head assembly of  claim 15 , wherein the fluid passageway is sealed between the one or more ports and the outlet so as to permit transportation of the reduced size rock fragments therebetween on application of a negative pressure or a suction pressure. 
     
     
         17 . The cutting head assembly of  claim 15 , wherein the outlet is proximal to the drive gear on the top of the housing and configured to connect to a suction pump of a miner body. 
     
     
         18 . The cutting head assembly of  claim 15 , wherein the drive gear is configured to engage a connecting gear of the miner body to thereby connect the cutting head assembly to a mining system via the miner body. 
     
     
         19 . (canceled) 
     
     
         20 . The cutting head assembly of  claim 17 , wherein the drive gear transmits a feed force from the miner body to the cutting head assembly. 
     
     
         21 . The cutting head assembly of  claim 20 , wherein the feed force is proportional to an applied weight of the miner body. 
     
     
         22 . The cutting head assembly of  claim 20 , wherein combination of the feed force and the breakage force of the primary breakage mechanism permit the cutting head assembly to engage and maintain engagement with the mine wall. 
     
     
         23 . A cutting head assembly for excavating rock fragments from a mine wall, the cutting head assembly comprising:
 a primary breakage mechanism actuable to apply, to the mine wall, a breakage force for breaking rock fragments from the mine wall;   a housing comprising a fluid passageway and a surface for catching the rock fragments broken from the mine wall, the surface having one or more ports associated therewith, wherein the fluid passageway extends between the one or more ports and an outlet;   a secondary breakage mechanism operatively associated with the surface and proximal to the one or more ports, the secondary breakage mechanism actuable to apply a force for reducing the size of at least some of the rock fragments caught by the surface so as to allow at least the reduced size rock fragments to pass through a respective port; and   wherein, in use, the secondary breakage mechanism actuates subsequent to the primary breakage mechanism and a suction pressure applied to the outlet transports the reduced sized rock fragments via the one or more ports to the outlet for downstream processing.   
     
     
         24 . A method for excavating rock fragments from a mine wall, the method comprising: providing a cutting head assembly according to  claim 1 ; and operating the cutting head assembly to excavate the rock fragments from the mine wall. 
     
     
         25 . (canceled) 
     
     
         26 . A system for mining excavating rock fragments from a mine wall, the system including: a cutting head assembly according to  claim 1 ; means controlling operation of the cutting head assembly to excavate rock fragments from the mine wall to provide a supply of rock fragments for processing; and processing means for processing the supply of rock fragments.