BOTTOM-HOLE MOTOR Russian patent published in 1998 - IPC

FIELD: drilling machinery and equipment. SUBSTANCE: bottom-hole motor is intended for use in drilling bore-holes. Motor has internal gear with external toothing and external gear with internal toothing. Both gears are kept in constant engagement. Gears are separated by non-rotating housing which carries internal gear. Passages are made in housing for delivery and discharge of working agent. Housing of motor is rigidly connected with drilling pipe string. External gear rotates due to energy of working agent flow. External gear of motor is rigidly connected with rock-crushing tool. Aforesaid embodiment of bottom-hole motor increases its efficiency and prolongs its service life. EFFECT: higher efficiency. 1 cl, 2 dwg