Apparatus for automated application of hardfacing material to drill bits

1. A system for depositing hardfacing material on portions of a drill bit comprising:

a first robot having a program controllable articulated arm connected to a plasma transfer arc torch secured thereto having a nozzle, the first robot programmed to position the torch over a surface of a portion of the drill bit in a desired plane thereabove prior to application of hardfacing material to a portion of the drill bit and to oscillate the torch relative to the portion of the drill bit;

a plasma gas supply to the torch having an electrically controllable flow valve;

a shielding gas supply to the torch having an electrically controllable flow valve;

a transport gas supply to the torch having an electrically controllable flow valve;

a powder dosage system connected to the transport gas supply;

a second robot having a program controllable articulated arm, the second robot programmed to position a surface of a cutter in a substantially horizontal plane below the torch prior to the application of hardfacing material to the cutter;

a jawed chuck attached to the program controllable articulated arm of the second robot, the jawed chuck securing a rock bit cutter;

at least one sensor for determining a location of a surface of the cutter; and

a programmable control system electrically connected to the first robot, the second robot, and the at least one sensor.

2. A system for depositing hardfacing material on a drill bit comprising:

a torch positioner having program controllable motion in a vertical plane;

a plasma transfer arc torch secured to the torch positioner in a substantially vertical orientation and having a nozzle directed downward;

a plasma gas supply to the torch having an electrically controllable flow valve;

a shielding gas supply to the torch having an electrically controllable flow valve;

a transport gas supply to the torch having an electrically controllable flow valve;

a powder dosage system connected to the transport gas supply;

a robot having a program controllable articulated arm;

a jawed chuck attached to the program controllable articulated arm, the jawed chuck securing a rock bit cutter;

at least one sensor for determining a location of a surface of the cutter;

a programmable control system electrically connected to the torch positioner, the torch, the robot, and the at least one sensor;

wherein the robot is programmed to position a surface of the cutter in a substantially horizontal plane below the torch prior to application of hardfacing material to the cutter; and

wherein the torch positioner is programmed to oscillate the torch along a substantially horizontal axis.

3. The system of claim 2 , further comprising:

the torch positioner being programmed to move the torch in a vertical axis; and

wherein movement of the torch along the vertical axis controls a voltage output of the torch.

4. The system of claim 2 , further comprising:

an electrically grounded adapter plate attached to the program controllable articulated arm; and

the jawed chuck attached to the adapter plate.

5. The system of claim 4 , further comprising:

the jawed chuck having three jaws;

each jaw having a cylindrical segment portion engaging an internal journal race portion of the cutter; and

each jaw having a torus segment portion adapted to receive an internal ball race portion of the cutter.

6. The system of claim 2 , further comprising:

an adapter being aligned to run substantially true with a programmable axis of the robot's movement.

7. The system of claim 2 , further comprising:

the jawed chuck being aligned by indicator positioning with a tapered flange to rotate within a 0.005 inch rotational tolerance.

8. The system of claim 2 , further comprising:

an adapter plate attached to the program controllable articulated arm;

the jawed chuck attached to an adapter; and

a heat sink provided between the adapter plate and the cutter.

9. The system of claim 2 , further comprising:

an air gap provided between the cutter and the jawed chuck.

10. The system of claim 2 , further comprising:

a thermal insulting material attached to the jawed chuck.

11. The system of claim 2 , further comprising:

the torch having a shielding gas cup surrounding an anode; and

the anode being liquid cooled.

12. The system of claim 2 , further comprising:

the torch having a shielding gas cup surrounding an anode; and

the shielding gas cup having a length of less than 4.40 inches.

13. The system of claim 2 , further comprising:

the torch having a shielding gas cup surrounding an anode; and

the shielding gas cup extending beyond the anode by less than 0.020 inch.

14. The system of claim 2 , further comprising:

the torch having a shielding gas cup surrounding an anode; and

the shielding gas cup having a diameter of less than 0.640 inch.

15. The system of claim 2 , further comprising:

the torch having a shielding gas cup surrounding an anode; and

an insulating material attached to an exterior of the gas cup portion of the torch.

16. The system of claim 2 , further comprising:

an imaging sensor directed to an area of a tooth being hardfaced.

17. The system of claim 2 , further comprising:

an imaging sensor electrically connected to the programmable control system.

18. The system of claim 2 , further comprising:

the flow valve of the shielding gas supply being program controllable by the programmable control system; and

a flow rate of the shielding gas supply being progressively increased to prevent porosity.

19. The system of claim 2 , further comprising:

filler material feed rates being controllable by the programmable control system.

20. The system of claim 2 , further comprising:

an electrical current supplied to the torch being controllable by the programmable control system.