Bearing support structure for the drive shaft from deep drilling chisels

摘要

An improved bearing system for the driven shaft of a downhole motor is shown that provides a main thrust and radial bearing system (28, 30) having means (34) for sealing the bearings in oil at equal or slight pressure above that of the drilling mud inside the drill pipe (10) and insulating the fluid seals and bearings from all possibility of contact with cuttings and debris from the drilling operation. A durable seal (44) having a restricted flow path permitting slow leakage is positioned below the main bearing system in such a relationship to the drilling fluid distribution path that the seals for the oil bath for the bearings are subjected to essentially the same pressure on all sides.