ROLLER-BIT DRILLING MACHINE Russian patent published in 1997 - IPC

FIELD: mining industry; roller-bit drilling facilities. SUBSTANCE: machine has mast, drilling head with drilling tool, rope-and-pulley system with hydraulic cylinders with feed drive. Hydraulic control valve of feed drive hydraulic cylinders has control chambers for lifting and lowering of drill string. Compressor is connected with drilling tool by compressed air line. Hydraulic pump unit is connected with hydraulic cylinders of rope-and-pulley system drive unit and incorporates sections for feeding drill string and for round trip operations. Sensors of axial thrust and air pressure are connected respectively with feed drive hydraulic cylinders and compressed air line. Also provided are vibration and electric current sensors. Machine has comparison blocks with set-point devices for maximal and minimal axial thrust, and control unit. First inlets of comparison blocks of maximal and minimal axial thrust are connected to axial thrust sensor, second inlets are connected to corresponding set-point devices, inlets of control unit are connected respectively to comparison block of minimal axial thrust and through second logic unit "OR" to comparison block of maximal axial thrust. EFFECT: high efficiency.