Phase cooling method and apparatus

1. A method of cooling at least one of a workpiece and a tool, the method comprising:

heating a coolant to a temperature within 10° C. of a phase change temperature at which the coolant will change phase from liquid to gas; and

subjecting at least one of the workpiece and the tool to the heated coolant in liquid form such that heat transfer to the coolant from at least one of the workpiece and the tool will cause the coolant to change phase from liquid to gas.

2. A method according to claim 1 wherein heating the coolant comprises heating the coolant to within 5° C. of the phase change temperature.

3. A method according to claim 1 wherein heating the coolant comprises heating the coolant to within 1° C. of the phase change temperature.

4. A method of cooling at least one of a workpiece and a tool, the method comprising:

heating a coolant to a temperature within 10° C. of a phase change temperature at which the coolant will change phase from liquid to gas;

subjecting at least one of the workpiece and the tool to the heated coolant in liquid form such that heat transfer to the coolant from at least one of the workpiece and the tool will cause the coolant to change phase from liquid to gas; and

drawing the coolant in gaseous form away from at least one of the workpiece and the tool.

5. A method according to claim 4 further comprising condensing the gaseous coolant such that the coolant changes phase from gas to liquid.

6. A method of cooling at least one of a workpiece and a tool, the method comprising:

heating a coolant to a temperature within 10° C. of a phase change temperature at which the coolant will change phase from liquid to gas;

subjecting at least one of the workpiece and the tool to the heated coolant in liquid form such that heat transfer to the coolant from at least one of the workpiece and the tool will cause the coolant to change phase from liquid to gas; and

aspirating the coolant prior to subjecting at least one of the workpiece and the tool to the heated coolant.

7. An apparatus for cooling at least one of a workpiece and a tool, the apparatus comprising:

a source of coolant that has been heated to a temperature within 10° C. of a phase change temperature at which the coolant will change phase from liquid to gas; and

a transport element for directing the heated coolant in liquid form from said source for eventual delivery to at least one of the workpiece and the tool such that heat transfer to the coolant from at least one of the workpiece and the tool will cause the coolant to change phase from liquid to gas.

8. An apparatus according to claim 7 wherein said source provides coolant that is within 5° C. of the phase change temperature.

9. An apparatus according to claim 7 wherein said source provides coolant that is within 1° C. of the phase change temperature.

10. An apparatus for cooling at least one of a workpiece and a tool, the apparatus comprising:

a source of coolant that has been heated to a temperature within a predefined range of a phase change temperature at which the coolant will change phase from liquid to gas;

a transport element for directing the heated coolant in liquid form from said source for eventual delivery to at least one of the workpiece and the tool such that heat transfer to the coolant from at least one of the workpiece and the tool will cause the coolant to change phase from liquid to gas; and

at least one of a condenser or a Venturi pump for drawing the coolant in gaseous form away from at least one of the workpiece and the tool.

11. An apparatus according to claim 7 wherein the condenser is further configured to condense the gaseous coolant such that the coolant changes phase from gas to liquid.

12. An apparatus for cooling at least one of a workpiece and a tool, the apparatus comprising:

a source of coolant that has been heated to a temperature within a predefined range of a phase change temperature at which the coolant will change phase from liquid to gas, wherein said source comprises:

a vessel in which the coolant is heated to an intermediate temperature; and

an induction head for receiving the coolant at the intermediate temperature from the vessel and for further heating the coolant to within the predefined range of the phase change temperature; and

a transport element for directing the heated coolant in liquid form from said source for eventual delivery to at least one of the workpiece and the tool such that heat transfer to the coolant from at least one of the workpiece and the tool will cause the coolant to change phase from liquid to gas.

13. An apparatus according to claim 12 wherein said transport element comprises a conduit extending from said vessel to said induction head.

14. An assembly comprising:

a bit to be cooled by coolant circulated therethrough;

a source of coolant that has been heated to a temperature within 10° C. of a phase change temperature at which the coolant will change phase from liquid to gas; and

a transport element for directing the heated coolant in liquid form from said source for eventual delivery to and circulation through the bit such that heat transfer to the coolant from the bit will cause the coolant to change phase from liquid to gas.

15. An assembly according to claim 14 wherein said source provides coolant that is within 5° C. of the phase change temperature.

16. An assembly according to claim 14 wherein said source provides coolant that is within 1° C. of the phase change temperature.

17. An assembly according to claim 14 further comprising a Venturi pump for drawing the coolant in gaseous form away from the bit.

18. An assembly according to claim 14 wherein said source comprises:

a vessel in which the coolant is heated to an intermediate temperature; and

an induction head for receiving the coolant at the intermediate temperature from the vessel and for further heating the coolant to within the predefined range of the phase change temperature.

19. An assembly according to claim 18 wherein said transport element comprises a conduit extending from said vessel to said induction head.