Abstract: An electrical linear motor for propelling a marine vessel through a liquid medium, comprises a housing secured to the marine vessel and submerged in the liquid medium, an insert within the housing and having at least two electrical coil windings disposed on internal walls of the insert; a thruster subassembly moves between the internal walls of the insert, the thruster subassembly having a front cover, an internal channel with check valve and at least two sets of permanent magnets attached to the thruster subassembly and maintained in sufficiently close proximity to the electrical coil windings so that an electromagnetic field created by a controlled energizing of the electrical coil windings interacts with a magnetic field from the permanent magnets to provide a resulting linear force, which causes a reciprocating linear motion of the thruster subassembly, wherein the check valve is in an open position during a back stroke of the thruster subassembly so that the liquid medium flows freely through the thruste

Abstract: An electrical linear motor for propelling a marine vessel through a liquid medium, comprises a housing secured to the marine vessel and submerged in the liquid medium, an insert within the housing and having at least two electrical coil windings disposed on internal walls of the insert; a thruster subassembly moves between the internal walls of the insert, the thruster subassembly having a front cover, an internal channel with check valve and at least two sets of permanent magnets attached to the thruster subassembly and maintained in sufficiently close proximity to the electrical coil windings so that an electromagnetic field created by a controlled energizing of the electrical coil windings interacts with a magnetic field from the permanent magnets to provide a resulting linear force, which causes a reciprocating linear motion of the thruster subassembly, wherein the check valve is in an open position during a back stroke of the thruster subassembly so that the liquid medium flows freely through the thruste

Abstract: An electrical linear motor for propelling a marine vessel comprises a thruster assembly disposed within a guide tube. Permanent magnets are attached to the thruster assembly and placed in close proximity to electrical coil windings, which are positioned outside of and parallel to the guide tube. Electrical current energizing the coil windings creates an electromagnetic field, which interacts with the magnetic field of the magnets to cause reciprocating linear motion of the thruster assembly with the guide tube. During the non-propelling back stroke, a check valve on the thruster assembly is in open position to allow free passage of water. The check valve is moved to a closed position during the working stroke of the thruster assembly, allowing the thruster assembly to propel the marine vessel.

Abstract: A magnetostrictive method and apparatus for propelling an object through a medium wherein one end of a magnetostrictive rod is firmly attached to a housing connected to the object and the other end of the rod is in contact, direct or through a flexible membrane, with the medium. Magnetic field pulses are created by energizing a coil located radially around and proximate to the magnetostrictive rod, said magnetic field pulses causing the rod to rapidly expand and contract longitudinally, in the presence and absence, respectively, of the magnetic field. A plurality of magnetostrictive rods can also be used to propel the object.

Abstract: Pulse rates, rise and fall times of pulses and lifetimes of mud pulsing valves are substantially increased by providing a valve with a plurality of openable ports which simultaneously open and close to provide a collective flow path of the mud through the valve. By employing a plurality of ports, instead of one port, the time rate of change in the flow area, as the plurality of ports opens and closes, is substantially greater in the case of a single port. As a result, mud velocity falls much more quickly and the abrasion damage within the mud valve is less. The rate of change of the flow area on opening and closing is further increased by providing noncircular ports. In particular, trapezoidal ports are utilized so that they open across a corresponding straight edges. A plurality of such trapezoidal ports may be utilized to increase the rate of change of flow area with time to an even greater extent.

Abstract: This invention is a dual axis, continuous flow centrifuge apparatus and method. A centrifuge head rotates in a vertical orientation about a first axis which, in turn, is rotated in a horizontal plane about a second axis. The rotation of the centrifuge head is matched to the rotation of the second axis to cancel out any net rotation of flexible conduits attached to the centrifuge head. The nonrotating coupling of the conduits permits continuous flow through the centrifuge head in the absence of seals. An angled centrifuge chamber inside the centrifuge head provides a more rapid separation of the components in the liquid passing through the centrifuge head. The path of travel of a particle in a centrifuge chamber inside the centrifuge head follows a generally cycloidal path thereby undergoing a pulsatile centrifugal force component.

Abstract: Multistate mud pulsing is achieved by generating both positive and negative pulses within a drill string by means of a plurality of selectively operable bypass passages around a restriction to primary mud flow within a drill string or by venting to outside of the drill string. A fraction of the hydraulic mud is drawn from a location upstream from the restriction into a valve manifold. The removed fraction of hydraulic mud is selectively communicated from the valve manifold either to a point inside a drill string downstream from the restriction or to a point exterior to the drill string in annulus between the outside of the drill string in the borehole. Mud reinjected downstream from the restriction creates a positive pressure pulse within the drill string. Mud which is diverted to the annulus outside of the drill string creates a negative mud pulse within the drill string.

Abstract: A logging-while-drilling tool includes a housing positioned in a drill string, a shaft journaled in the housing, a turbine stage or stages, a rotor or rotors, the latter mounted on the shaft outside of the housing and driven by the drilling fluid and a braking device for variably controlling the rotational speed of the rotor in order to produce pressure pulses which are transmitted to the surface through the drilling fluid. A generator or other energy storing device is provided to power an electronic package which interprets downhole conditions for transmission of the same as pressure pulses.

Abstract: Multistate mud pulsing is achieved by generating both positive and negative pulses within a drill string by means of a plurality of selectively operable bypass passages around a restriction to primary mud flow within a drill string or by venting to outside of the drill string. A fraction of the hydraulic mud is drawn from a location upstream from the restriction into a valve manifold. The removed fraction of hydraulic mud is selectively communicated from the valve manifold either to a point inside a drill string downstream from the restriction or to a point exterior to the drill string in annulus between the outside of the drill string in the borehole. Mud reinjected downstream from the restriction creates a positive pressure pulse within the drill string. Mud which is diverted to the annulus outside of the drill string creates a negative mud pulse within the drill string.