Turbo-drill

Claim 1

A turbo-drill comprising: a housing including means at its upper end for connection to the lower end of a string of drill pipes; a shaft disposed in said housing on supports including means for mounting a drill bit; a supporting unit to transmit the force to the drilling bit from said string of drill pipes, said supporting unit being arranged under said housing with said shaft arranged therein and connecting the shaft to the drilling bit; stators secured in said housing and provided with races and vanes forming guiding channels for passing therethrough a flushing fluid pumped from the surface through said string of drill pipes to activate said turbo-drill, said flushing fluid flowing throughout the entire lenght of said turbo-drill and through said drilling bit to a hole bottom being drilled, and the fluid returning upward through a space around the pipes; rotors mounted on said shaft for relative rotation with respect to said shaft, said rotors having races and vanes facing in a direction opposite to that of said vanes of the stators for transforming the translational motion of said flushing fluid into rotational motion of said rotors; carriers with rolling bodies disposed therein which are located between said races of said stators and rotors and connected to said shaft, said rolling bodies being disposed between said races of the stators and rotors and forming, together with said carriers, stators and rotors, reduction stages of an axial reduction turbine wherein said rotors form a driving inner wheel, said stators forming an outer wheel, and said rolling bodies forming idlers, said races of the rotors being located in an operative position above the respective races of the stators, as a result of which downward axial force developing on said rotors during the translational motion of the flushing fluid through said reduction stages presses said rolling bodies against said races of the stators and rotors so that contact friction forces are generated between said rolling bodies and said races of the stators and rotors and transmit torque through the idler elements to the drilling bit, the stator vanes forming channels for the passage of flushing fluid, and the rotors having vanes face in a direction opposite to that of said vanes of the stators, forming reductionless stages of the turbine and are mounted between and above said reduction stages so that the stators are fixedly positioned in said housing, and the rotors are mounted on the shaft and adapted to move axially so as to be pressed with their lower end faces, under the effect of the downward axial force generated during the translational motion of the flushing fluid on the vanes of said rotors of the reductionless stages of the turbine to the upper end faces of the rotors of the underlying reduction stages, thereby increasing the force with which said rolling bodies are pressed against said races of the stators and rotors of the reduction stages.