A downhole drilling motor assembly includes a first motor, a second motor aligned coaxially with the first motor, and a clutch assembly aligned coaxially with the first and second motors. The clutch assembly independently and selectively actuates each of the first and second motors to rotationally drive a drill bit. A related method includes: mounting a drill bit at a distal end of a drill string at a well site; and providing a downhole drilling motor assembly which rotationally drives the drill bit. The clutch assembly is controlled to independently and selectively actuate the first and second motors, and the drill bit is rotationally driven via the independent and selective actuation of the first and second motors.

A motor system including: a cylindrical body; a converter configured to convert a two-directional rotation into a one-directional rotation; a rotatable shaft configured to be (a) disposed inside of the cylindrical body, (b) rotatable in both a counterclockwise direction and a clockwise direction, and (c) coupled to a drill bit through the converter; a driving piston configured to be coupled to the rotatable shaft and configured to divide the cylindrical body into a first chamber and a second chamber; and a flow piston configured to change flow direction of the fluid within the cylindrical body to drive the driving piston, wherein the driving piston is configured to be driven by the fluid via a pressure difference to move in a forward direction and in a reverse direction.

An electrical submersible well pump assembly (ESP) has a spring brake having helical turns mounted between the shaft and one of the housings. The spring brake allows free rotation of the shaft in a driving direction and stops the shaft from rotating in a reverse direction. The spring brake may have one end be affixed to the housing to rotate in unison in both directions. Alternately, the spring brake may have one end affixed to the shaft for rotation with the shaft. Further, the spring brake could be free of being connected to either the shaft or the housing. A shear member may be mounted between the shaft and the housing to prevent any rotation of the shaft during run-in.

Unlaminated bearings (or Torque Transfer Elements, or TTEs) are disposed to slide and displace within pockets (or “housing cavity receptacles”) provided in the internal periphery of a housing in which an articulating shaft is received. As the shaft “tilts” about its untilted axial centerline during misaligned rotation, convex curved bearing surfaces on shaft pins slidably rotate against corresponding concave curved bearings surfaces on the T as received in the housing cavity receptacles. Further, substantially flat surfaces on the TTEs are disposed to slidably displace against corresponding bearing surfaces on the housing cavity receptacles as the shaft tilts and the convex curved bearing surfaces on the shaft pins slidably rotate against the concave curved bearing surfaces on the TTEs. The sliding displacement of TTEs with respect to the housing cavity receptacles during articulated rotation is in a direction generally parallel to the shaft's untilted axial centerline.

The invention relates to a rotary drive arrangement for a drill rod having an outer pipe and an inner rod running at least in sections inside the outer pipe, in particular for double-head and/or overburden drilling, with a first gearbox for driving the inner rod in a rotating manner and a second gearbox for driving the outer pipe in a rotating manner, wherein the first gearbox and the second gearbox are independent of each other. According to the invention provision is made in that the first gearbox and the second gearbox are supported in a common gearbox housing and are surrounded by the same.

A rotary actuator assembly can include a fluid motor with a rotor that displaces with hypocyclic precessional motion within a stator in response to fluid flow through the fluid motor, and a gear reducer section including an input gear that is fixed relative to the rotor and displaces with the hypocyclic precessional motion relative to an output gear. Another rotary actuator assembly can include a fluid motor with a rotor having a central longitudinal axis that rotates about a central longitudinal axis of a stator, and a gear reducer section including an input gear that rotates with the rotor and displaces relative to an output gear, and the input gear having the same central longitudinal axis as the rotor. A well system can include at least two fluid motors, and fluid flow through one fluid motor causes rotation of the other fluid motor in the well.

A ground drilling device with a drivetrain for rotating a drill string, wherein at least one section of the drivetrain is configured to form a channel between a force transmission element of the drivetrain and the drill string, wherein the channel projects through the force transmission element and the force transmission element may be driven radially in the drivetrain.

A rotary transfer mechanism is disclosed for a motor, pump, or other downhole tool that accommodates the eccentric motion of a rotor without the need for a flex shaft, articulating joint or CV joint. In one configuration, the rotor is coupled to the drive shaft at a radial offset from the drive shaft axis. The orbiting motion of the rotor, rather than rotation of the rotor about its own axis, generates a torque on the drive shaft, by applying a tangential force to the drive shaft at the location of the radial offset. The radial offset may be set equal to the orbital radius so that no radial movement or flex is required at the drive shaft to accommodate the eccentric rotor movement.

The invention discloses an induced drilling method for inertial constraint implicated motion, which is characterized by comprising a motion step of separating weight on bit and torque. The induced drilling method of inertial constraint implicating motion comprises the following steps: step 1, model selection of induced drilling; step 2, potential energy storage of induced drilling, wherein step 2 includes: I, uniform cutting induced drilling under a steady condition; II, distribution of induced drilling shock wave propagation under a transient condition; III, potential energy release of torsion spring in induced drilling under the transient condition; IV, constrained buffer for induced drilling under transient conditions; and V, potential energy compensation for induced drilling under transient conditions. The invention also discloses an inertia constraint induced drilling device accompanying the PDC bit.

The present invention relates to a rotating self-drilling device for extraterrestrial objects. One end of a pressure sensor installing barrel is connected with a rear cover; a reed fixing lower cover is installed on the rear cover; one end of a wire outlet post is connected with the reed fixing lower cover, and the other end is provided with a reed fixing upper cover; a plurality of reeds are arranged between the reed fixing upper cover and the reed fixing lower cover; both ends of each of the reeds are respectively connected with the reed fixing upper cover and the reed fixing lower cover; the other end of the pressure sensor installing barrel is connected with one end of a motor installing barrel; the other end of the motor installing barrel is connected with a motor installing barrel front cover; a motor and decelerator is placed in the motor installing barrel; both ends of a transmission shaft are respectively connected with the output end of the motor and decelerator and a ferrule; both ends of a milling head are respectively connected with the ferrule and a drill bit; a propelling spiral tube is sleeved outside the motor installing barrel; both ends are respectively connected with the ferrule and a bearing fixing cover; the bearing fixing cover is rotatably connected with the motor installing barrel; The overall structure of the present invention is light and compact. A drive system has only one motor to realize large penetration depth.