Other

Donald L. Morton & Associates

University of California

William H Harrison

Mitsuaki A Arakawa

Lawrence E Crooks

Barry M McCarten

Llewellyn A Rubin

A directional borehole drilling system employs a controllable drill bit, which includes one or more conical drilling surfaces. Instrumentation located near the bit measures present position when the bit is static, and dynamic toolface when the bit is rotating. This data is processed to determine the error between the present position and a desired trajectory, and the position of one or more of the bit's leg assemblies is automatically changed as needed to make the bit bore in the direction necessary to reduce the error. The controllable drill bit preferably comprises three leg assemblies mounted about the bit's central axis, each leg having a 'toed-out' axle. In response to a command signal, a lower leg translates along the bit axis to cause it to bear more of the bit weight, thus excavating more deeply over the commanded toolface sector and causing the bit to bore in a preferred direction.

Directional borehole drilling system and method

A directional borehole drilling system employs a controllable drill bit, which includes one or more conical drilling surfaces. Instrumentation located near the bit measures present position when the bit is static, and dynamic toolface when the bit is rotating. This data is processed to determine the error between the present position and a desired trajectory, and the position of one or more of the bit's cones is automatically changed as needed to make the bit bore in the direction necessary to reduce the error. The controllable drill bit preferably comprises three cone assemblies mounted about the bit's central axis, each of which includes a leg with &ldquo;toed-out&rdquo; axle. In response to a command signal, a cone translates along the axle to cause it to bear more of the bit weight, thus excavating more deeply over the commanded toolface sector and causing the bit to bore in a preferred direction.

A directional borehole drilling system employs a controllable drill bit, which includes one or more drilling surfaces which are dynamically positionable in response to respective command signals. Instrumentation located near the bit measures present position when the bit is static, dynamic and drilling surface position information when the bit is rotating, and stores a desired trajectory. This data is processed to determine the error between the present position and the desired trajectory, and the position of one or more of the bit's drilling surfaces is automatically changed as needed to make the bit dig in the direction necessary to reduce the error. The controllable drill bit preferably comprises three cone assemblies mounted about the bit's central axis, each of which includes a cone and an eccentric cam that rotate about a common axle. In response to a command signal, the cam is locked to the cone to cause concentric rotation of the cone, or locked to the axle to cause eccentric rotation of the cone&mdash;which causes the bit to dig in a preferred direction.

The RF coil and transmission line of a Magnetic Resonance Imaging (MRI) system are remotely tuned for variation from matched impedance conditions (e.g., as caused by variable loading of the RF coil by objects to be imaged which vary from an assumed median object) via a pair of series-connected over-coupled parallel-resonant circuits, each of which includes an adjustable capacitance.

Remotely adjustable MRI RF coil impedance matching circuit with mutualy

An electrostatic deep heating applicator deposits RF energy in a relatively uniform manor throughout a given cross-section of the human torso, thus resulting in a similar uniform heating of the region. The applicator uses a pair of identical, rectangular or cylindrical applicators which generate a heat-producing electric field predominantly parallel to the major axis of the body so as to minimize excessive surface heating. The applicator finds particular use in the treatment of deep seated cancers in patients. Its dimensions allow a relatively large circumferential air gap when placed around the torso so that it is convenient to use and is non-threatening to the patient.

Electrostatic deep heating applicator

An electrostatic deep heating applicator deposits RF energy in a relatively uniform manor throughout a given cross-section of the human torso, thus resulting in a similar uniform heating of the region. The applicator uses a pair of identical, rectangular, flat or cylindrical applicators which generate a heat-producing electric field predominantly parallel to the major axis of the body so as to minimize excessive surface heating. The applicator finds particular use in the treatment of deep seated cancers in patients. It need only be placed near the torso for satisfactory operation, thus allowing a relatively large air gap between it and the patient. It requires very minimum set-up time, is convenient to use and is non-threatening to the patient.

Electrostatic deep heating applicators

A quadrature detection MRI radio frequency coil includes plural axially-extending conductive legs. At least two of the legs include breaks in conductivity at their mid-point with circumferentially extending inner-bridge conductors connected thereacross to which RF input/output feed connections are conveniently made so as to achieve a center fed coil structure, open at both ends. Other axially-extending legs may also include conductive breaks with capacitive coupling thereacross and circumferentially extending outer-bridges between the outer or distal ends of the legs may also include breaks in conductivity with capacitive coupling thereacross.

Center fed QD MRI RF coil

A system and method is described for amplifying and transmitting an information signal from a downhole drillstring location. The amplifier shifts the relatively low frequency information signal up to a high frequency level, amplifies the high frequency signal and processes it through an impedance matching transformer, and then demodulates the amplified signal back to the original low frequency for transmission through the earth to the surface, thus enabling the use of a much smaller transformer than when the information signal is processed entirely at the low frequency level. A novel transducer consisting of generally cylindrical conductive sleeves separated by an insulative gap is used to provide structural integrity and to transmit the amplified information signal. The conductive sleeves are heat shrunk onto an insulative sleeve and a central mandrel.

Downhole telemetry apparatus and method

Undesirable RF coupling via the outside of an outer coaxial cable conductor to/from RF coils in a magnetic resonance imaging apparatus is minimized by employing a parallel resonance tuned RF choke in the circuit. The choke is realized by forming a short coiled section of the coaxial cable with a lumped fixed capacitance connected in parallel thereacross and a conductive tuning rod positioned within the center of the coiled section so as to trim the parallel resonant frequency to the desired value.

RF coil coupling for MRI with tuned RF rejection circuit using coax

An electrode of the self-resonant, single-turn loop type adapted for attachment to a source of radio frequency energy to produce deep-heating by hyperthermia. The electrode is characterized by being a long cylindrical electrode having a small diameter to length radio as, for example, 0.5 to 1. The electrode is in the form of a cylinder having a gap along one side to which a plurality of capacitor plates are electrically connected radially outward and in parallel spaced relationship with a dielectric material disposed therebetween.

Therapeutic magnetic electrode

An electrode for use in the treatment of animal tissue by hyperthermia particularly adapted for use in the neck regions wherein a planar field of energy is required so as to concentrate therapeutic energy in the area of a plane passing through the electrode with very little energy available to affect adjacent areas beyond close proximity to the plane of the electrode. In the preferred embodiment the electrode comprises disk segments of a conductive material disposed in overlapped relationship on either side of dielectric material to form conductive annular disks separated by dielectric material so as to be a single self-resonant loop.

Planar disc magnetic electrode

A self-resonant single-turn electrode for use in the treatment of animal tissue with hyperthermia by coupling the electrode to a supply of radio frequency energy. The electrode comprises a plurality of planar annular disc members concentrically stacked with dielectric material therebetween. Each disc has a radial slit therethrough to form a gap. The discs are stacked with the gaps of adjacent discs 180.degree. apart. The radio frequency energy may be coupled to the entire stack by connecting to only one disc and the discs are all insulated from each other.

Multiple plate resonant electrode

The present invention discloses an improved electrode for use with apparatus employing radio frequency energy for deep heating of materials. In particular, it is adapted for the medical treatment of living animal tissue by hyperthermia. The electrode comprises a single loop turn having capacitance associated therewith so as to resonate the electrode for maximum power transfer thereto. The electrode causes a field to be generated within the annular region enclosed by the electrode comprising a plurality of concentric, substantially equally powered lines of force in which the living tissue to be treated is disposed. The electrode finds particular use in the treatment of deep seated cancers in patients.

Deep heating electrode

An electrode of the type used in the treatment of animal tissue by hyperthermia wherein a self-resonant single turn loop electrode creates a field of electromagnetic energy. The electrode comprises three plate members forming the sides and bottom of a box-like area in which the patient is positioned. The fourth electrode is vertically disposed above the patient and between the two side members being arcuate in shape on the edge adjacent the patient and normal to the other members. The two side members are disconnectable from the back member so that the back member can be positioned beneath a patient's mattress and the side members and arcuate member then placed over the patient in operable position when desired.

Portable body electrode

A brake assembly for skateboards which allows smooth, safe, trouble-free braking. The assembly includes a pivotal, wheel-engaging brake plate and a depressible foot-operated pedal coupled to the plate for selective shifting of the latter into frictional, braking engagement with the wheel. A pair of debris-clearing brushes are also mounted on the brake assembly and assist in braking when the pedal is depressed. A secondary, stationary brush member is also mounted adjacent the remaining wheel assembly for debris-clearing purposes.

Growing community of inventors

Woodland Hills, CA, United States of America

William H Harrison