WELL-SINKING DEVICE Russian patent published in 1997 - IPC

FIELD: construction, applicable for well-sinking without excavation of soil. SUBSTANCE: the device uses a motor-reduction gear, working member in the form of a cantilever shaft, taper and cylindrical sections with rolls installed on the shaft and shifted at an angle to the shaft longitudinal axis. The rolls can freely rotate and come in contact with the soil. At screwing in the soil each roll rotates in the opposite direction of rotation of the working member shaft with a constant transmission ratio. Eccentricities of the cylindrical rolls are equal to the maximum eccentricity of the taper rolls. EFFECT: enhanced performance due to stabilization of the lead of screwing of the rolls and reduction of their taper angles. 2 dwg