Thermal drilling device
Patent 4076082 Issued on February 28, 1978. Estimated Expiration Date: 
February 28, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.
February 28, 1995. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent References 2266834 2638976 2725929 3172457 3182734 3358783 3687375 3756511 InventorsAssigneeApplicationNo. 05/734424 filed on 10/21/1976US Classes:175/14, Combustion is confined chamber having restricted discharge orifice266/904, BLOWPIPE CUTTING HEADS431/158Chamber outlet forms jet nozzleExaminersPrimary: Purser, Ernest R.Assistant: Favreau, Richard E. Attorney, Agent or FirmInternational ClassE21B 7/14 (20060101)Foreign Application Priority Data1976-02-20 DTAbstractA thermal drilling device which operates in a rotary or circumferentially oscillatory motion and which is particularly adapted for drilling geological formations comprises a drill body which has an interior combustion chamber with a bottom having an outlet defining a discharge nozzle. Means are provided for adding fuel components into the combustion chamber and for igniting them to generate hot gaseous products of combustion which are discharged through a nozzle slot arranged at the bottom of the combustion chamber. The nozzle slot extends diametrically of the drilling area at the bottom and slot outline or a plurality of slots arranged symmetrically relative to the longitudinal axis of the drilling body. In one embodiment the nozzle slot has a radially extending portion with the circumferential width of the slot increasing in a radial outward direction. | |
