POWER SECTION AND TRANSMISSION OF A DOWNHOLE DRILLING MOTOR

摘要

Present embodiments of the disclosure are directed to power section and transmission components within a downhole drilling motor that may reduce or eliminate axial thrust loads on the transmission of the drilling motor. The transmission may utilize a driven shaft coupled between two connectors that enable torque transfer to and from the transmission while allowing the driven shaft to move freely in two planes. The power section may include a rotor with a through bore and a flex-shaft disposed in the through bore. The flex-shaft may be designed to rotate with the rotor. The flex-shaft may extend beyond the length of the rotor in one direction to be centralized within a bearing assembly. The opposite end of the flex-shaft may include a load-carrying shoulder that is retained in the bottom end of the rotor.

主权项

1. A transmission coupling for use in a downhole drilling motor, comprising:
a shaft for transmitting torque from an upstream power section of the downhole drilling motor to a drive shaft of the downhole drilling motor; a first connector disposed over a first end of the shaft to couple the first end of the shaft to a first component of the downhole drilling motor; a first pair of ball bearings disposed between the shaft and the first connector, wherein the first pair of ball bearings are radially offset from each other by approximately 180 degrees about a longitudinal axis of the shaft; and a first sliding connection disposed between the shaft and the first connector to enable the first pair of ball bearings to move opposite from one another in a direction substantially parallel to an axis of the first connector.