Subassembly for a directional drilling system

Abstract

A subassembly for a directional drilling system that includes a drill bit that rotates about a longitudinal axis. The drill bit includes an inlet for receiving drilling fluid and an outlet for allowing drilling fluid to exit the drill bit. The flow direction of drilling fluid exiting the drill bit is determined by a rotary position of a flow diverter about the longitudinal axis of the subassembly. The subassembly also includes a housing portion connected to the drill bit. The subassembly further includes a motor assembly positioned within the housing portion. The motor assembly includes a motor assembly housing rotatably fixed to the housing portion and a drive shaft rotatable relative to the motor assembly housing. The drive shaft is coupled to the flow diverter, and the motor assembly is configured to operate the drive shaft to control the rotary position of the flow diverter.

1 .- 42 . (canceled) 
     
     
         43 . A subassembly for a directional drilling system configured to drill a wellbore, the subassembly comprising:
 a drill bit configured to rotate about a longitudinal axis of the subassembly in a first direction, the drill bit comprising an inlet for receiving drilling fluid and an outlet for allowing drilling fluid to exit the drill bit;   a flow diverter configured to rotate about the longitudinal axis of the subassembly in a second direction, wherein the flow direction of drilling fluid exiting the drill bit is determined by a rotary position of the flow diverter about the longitudinal axis of the subassembly;   a housing portion connected to the drill bit;   a motor assembly positioned within the housing portion, the motor assembly comprising a motor assembly housing rotatably fixed to the housing portion and a drive shaft rotatable relative to the motor assembly housing, the drive shaft being coupled to the flow diverter; and   wherein the motor assembly is configured to operate the drive shaft to control the rotary position of the flow diverter.   
     
     
         44 . The subassembly of  claim 43 , wherein the flow diverter is mounted on a flow diverter shaft and wherein the flow diverter shaft is connected to the drive shaft via a releasable coupling. 
     
     
         45 . The subassembly of  claim 44 , wherein the releasable coupling is a universal coupling. 
     
     
         46 . The subassembly of  claim 44 , wherein the releasable coupling is a Cardan coupling. 
     
     
         47 . The subassembly of  claim 43 , wherein the flow diverter is positioned within a cartridge, the cartridge being configured to be received within an internal space of the drill bit. 
     
     
         48 . The subassembly of  claim 47 , wherein the cartridge is removably-couplable to the drill bit. 
     
     
         49 . The subassembly of  claim 43 , wherein the motor assembly is fixed to the housing portion by a support member. 
     
     
         50 . The subassembly of  claim 49 , wherein the support member comprises one or more apertures for allowing drilling fluid to flow through the housing portion to the inlet of the drill bit. 
     
     
         51 . The subassembly of  claim 49 , wherein the support member is configured to position the motor assembly radially centrally within the housing portion. 
     
     
         52 . The subassembly of  claim 49 , wherein the support member is a support hanger. 
     
     
         53 . The subassembly of  claim 43 , wherein the motor assembly comprises an electric motor. 
     
     
         54 . The subassembly of  claim 53 , wherein the electric motor is a direct current motor and/or wherein the electric motor is a brushless motor. 
     
     
         55 . The subassembly of  claim 43 , wherein the outlet of the drill bit comprises a first outlet and a second outlet, wherein the flow diverter is configured to allow drilling fluid to flow between the inlet of the drill bit and the first outlet of the drill bit, and substantially prevent drilling fluid from flowing between the inlet of the drill bit and the second outlet of the drill bit, when the flow diverter is in a first rotary position and the drill bit is in a first rotary position. 
     
     
         56 . The subassembly of  claim 43 , wherein the flow diverter comprises an eccentric flow-diverting aperture for diverting the drilling fluid. 
     
     
         57 . The subassembly of  claim 43 , wherein the flow diverter is removably-couplable to the drill bit. 
     
     
         58 . The subassembly of  claim 43  comprising a generator for powering the motor assembly, wherein the generator is positioned within the housing portion. 
     
     
         59 . The subassembly of  claim 58 , wherein the generator is rotatably fixed to the housing portion. 
     
     
         60 . The subassembly of  claim 58 , wherein the generator comprises a turbine configured to be driven by the drilling fluid. 
     
     
         61 . A directional drilling system comprising:
 a drill string; and   a subassembly comprising:
 a drill bit configured to rotate about a longitudinal axis of the subassembly in a first direction, the drill bit comprising an inlet for receiving drilling fluid and an outlet for allowing drilling fluid to exit the drill bit; 
 a flow diverter configured to rotate about the longitudinal axis of the subassembly in a second direction, wherein the flow direction of drilling fluid exiting the drill bit is determined by a rotary position of the flow diverter about the longitudinal axis of the subassembly; 
 a housing portion connected to the drill bit; 
 a motor assembly positioned within the housing portion, the motor assembly comprising a motor assembly housing rotatably fixed to the housing portion and a drive shaft rotatable relative to the motor assembly housing, the drive shaft being coupled to the flow diverter; and 
 wherein the motor assembly is configured to operate the drive shaft to control the rotary position of the flow diverter. 
   
     
     
         62 . A kit of parts for forming a subassembly for a directional drilling system configured to drill a wellbore, the kit of parts comprising:
 a drill bit comprising an inlet for receiving drilling fluid and an outlet for allowing drilling fluid to exit the drill bit;   a flow diverter;   a housing portion connectable to the drill bit; and   a motor assembly positioned within the housing portion, the motor assembly comprising a motor assembly housing rotatably fixed to the housing portion and a drive shaft rotatable relative to the motor assembly housing and wherein the drive shaft is couplable to the flow diverter.