Abstract: A cannula for connecting a medical device to a biological system is taught. The cannula includes a tissue engagement portion, preferably in the form of an annulus, to which a vacuum is applied through the cannula to attract and hold tissue of the biological system in an initial connection while an affixment device is applied to complete the connection. In addition to a working fluid conduit, comprising a main port, a working fluid passage and a working fluid port, and a port to apply the vacuum, the cannula can include a sensor port to allow sensing pressure or other characteristics of the working fluid at a point closely adjacent to the connection between the cannula and the biological system.

Abstract: A steering assembly includes an outer housing and a drive shaft extended longitudinally within the outer housing and defining a plurality of pockets. A plurality of torque transfer features transfer torsional loads from the outer housing to the drive shaft, each torque transfer feature including a shank received within a corresponding one of the plurality of pockets. One or more elastic mounts positioned within each pocket interpose the shank and an inner wall of each pocket.

Abstract: A downhole steering assembly includes a steering element having an adjustable azimuthal orientation relative to a tool body. The downhole tool further includes a radio frequency identification (RFID) reader to read RFID tags arranged in an azimuthal arrangement. The downhole tool further includes an actuation mechanism that brings different RFID tags into range of the RFID reader. The downhole tool further includes a processor coupled to the RFID reader to determine an azimuthal orientation of the steering element and to responsively control the actuation mechanism.

Abstract: Methods and apparatus are disclosed for coupling components within a downhole motor drivetrain, and particularly to improving the torque carrying characteristics through threaded couplings in the drivetrain that extends between the mud motor and the drill bit. The described downhole motor drivetrain includes one or more threaded couplings, with each coupling configured to define a gap to accept a spacer having a dimension within a range of sizes. The dimension of the selected spacer placed in the threaded coupling facilitates establishing a desired balance of the force loading at each of two contact regions of the coupling. In many examples, the two contact regions of the coupling will be located on opposite sides of the threaded region.

Abstract: A driveshaft transmission assembly may include a coupling mechanism for coupling a radial bearing assembly to a driveshaft. The coupling mechanism may include a bearing cap for creating an interference fit with a downhole portion of the radial bearing assembly. The coupling mechanism may include locking pins and a retention sleeve to retain the locking pins in grooves of the driveshaft and openings in the radial bearing sleeve. The radial bearing assembly may include a catch mechanism for preventing the loss of certain driveshaft transmission assembly components downhole in the event of a failure of the driveshaft transmission. The coupling mechanism may prevent the loss of the driveshaft downhole subsequent to separation of certain driveshaft transmission assembly components.

Abstract: A rheological lock apparatus includes a fluid chamber formed within a housing between a pair of seals. The fluid chamber contains a rheological fluid. An inner surface of the housing has a first plurality of splines projecting into the fluid chamber and extending longitudinally along a longitudinal dimension of the chamber. A driveshaft extends axially through the chamber such that the pair of seals are sealed against the driveshaft. The driveshaft includes a second plurality of splines. A field generator is coupled to one of the driveshaft or the housing to generate a field through the rheological fluid during times when the housing is substantially immobile in a borehole.

Abstract: An interference apparatus is provided for a motor shaft transmission assembly. The interference apparatus may include split-ring shells and a retaining device. The interference apparatus may be mounted to an intermediate sleeve of the motor shaft transmission assembly. The interference apparatus is configured to prevent the loss of certain motor shaft transmission assembly components downhole in the event of a failure of the motor transmission due to dynamic loads.

Abstract: A rotationally selectable lock apparatus includes an outer element having a plurality of locking pins that are radially spring loaded to extend and retract through the outer element. An inner element is substantially encircled by the outer element and coupleable to a driveshaft. The inner element is configured to cause the plurality of locking pins to retract through the outer element in response to the driveshaft rotating in a first direction and extend through the outer element to engage a housing in response to the driveshaft rotating in a second direction, opposite to the first direction.

Abstract: A steering assembly includes an outer housing and a drive shaft extended longitudinally within the outer housing and defining a plurality of pockets. A plurality of torque transfer features transfer torsional loads from the outer housing to the drive shaft, each torque transfer feature including a shank received within a corresponding one of the plurality of pockets. One or more elastic mounts positioned within each pocket interpose the shank and an inner wall of each pocket.

Abstract: A rotationally selectable lock apparatus includes an outer element having a plurality of locking pins that are radially spring loaded to extend and retract through the outer element. An inner element is substantially encircled by the outer element and coupleable to a driveshaft. The inner element is configured to cause the plurality of locking pins to retract through the outer element in response to the driveshaft rotating in a first direction and extend through the outer element to engage a housing in response to the driveshaft rotating in a second direction, opposite to the first direction.

Abstract: An organ perfusion device includes an inlet for connection to the organ, and an outlet for connection to the organ. The device also includes a perfusion circuit including: a reservoir configured to hold a perfusion fluid; a waste receptacle, and a plurality of fluid conduits. The fluid conduits define: a delivery fluid path connecting the reservoir with the inlet; a return fluid path, independent of the delivery fluid path, connecting the reservoir with the outlet; and a waste fluid path connecting the reservoir with the waste receptacle. The device also includes a first flow control device configured to selectively prevent or allow fluid flow from the reservoir to the organ via the delivery fluid path; and a second flow control device configured to selectively prevent or allow fluid flow from the reservoir to the waste receptacle via the waste fluid path.

Abstract: An organ perfusion device includes an inlet for connection to the organ, and an outlet for connection to the organ. The device also includes a perfusion circuit including: a reservoir configured to hold a perfusion fluid; a waste receptacle, and a plurality of fluid conduits. The fluid conduits define: a delivery fluid path connecting the reservoir with the inlet; a return fluid path, independent of the delivery fluid path, connecting the reservoir with the outlet; and a waste fluid path connecting the reservoir with the waste receptacle. The device also includes a first flow control device configured to selectively prevent or allow fluid flow from the reservoir to the organ via the delivery fluid path; and a second flow control device configured to selectively prevent or allow fluid flow from the reservoir to the waste receptacle via the waste fluid path.

Abstract: Methods and apparatus are disclosed for coupling components within a downhole motor drivetrain, and particularly to improving the torque carrying characteristics through threaded couplings in the drivetrain that extends between the mud motor and the drill bit. The described downhole motor drivetrain includes one or more threaded couplings, with each coupling configured to define a gap to accept a spacer having a dimension within a range of sizes. The dimension of the selected spacer placed in the threaded coupling facilitates establishing a desired balance of the force loading at each of two contact regions of the coupling. In many examples, the two contact regions of the coupling will be located on opposite sides of the threaded region.

Abstract: A driveshaft transmission assembly may include a coupling mechanism for coupling a radial bearing assembly to a driveshaft. The coupling mechanism may include a bearing cap for creating an interference fit with a downhole portion of the radial bearing assembly. The coupling mechanism may include locking pins and a retention sleeve to retain the locking pins in grooves of the driveshaft and openings in the radial bearing sleeve. The radial bearing assembly may include a catch mechanism for preventing the loss of certain driveshaft transmission assembly components downhole in the event of a failure of the driveshaft transmission. The coupling mechanism may prevent the loss of the driveshaft downhole subsequent to separation of certain driveshaft transmission assembly components.

Abstract: An interference apparatus is provided for a motor shaft transmission assembly. The interference apparatus may include split-ring shells and a retaining device. The interference apparatus may be mounted to an intermediate sleeve of the motor shaft transmission assembly. The interference apparatus is configured to prevent the loss of certain motor shaft transmission assembly components downhole in the event of a failure of the motor transmission due to dynamic loads.

Abstract: A downhole steering assembly includes a steering element having an adjustable azimuthal orientation relative to a tool body. The downhole tool further includes a radio frequency identification (RFID) reader to read RFID tags arranged in an azimuthal arrangement. The downhole tool further includes an actuation mechanism that brings different RFID tags into range of the RFID reader. The downhole tool further includes a processor coupled to the RFID reader to determine an azimuthal orientation of the steering element and to responsively control the actuation mechanism.

Abstract: An organ perfusion device includes an inlet for connection to the organ, and an outlet for connection to the organ. The device also includes a perfusion circuit including: a reservoir configured to hold a perfusion fluid; a waste receptacle, and a plurality of fluid conduits. The fluid conduits define: a delivery fluid path connecting the reservoir with the inlet; a return fluid path, independent of the delivery fluid path, connecting the reservoir with the outlet; and a waste fluid path connecting the reservoir with the waste receptacle. The device also includes a first flow control device configured to selectively prevent or allow fluid flow from the reservoir to the organ via the delivery fluid path; and a second flow control device configured to selectively prevent or allow fluid flow from the reservoir to the waste receptacle via the waste fluid path.

Abstract: A cannula for connecting a medical device to a biological system is taught. The cannula includes a tissue engagement portion, preferably in the form of an annulus, to which a vacuum is applied through the cannula to attract and hold tissue of the biological system in an initial connection while an affixment device is applied to complete the connection. In addition to a working fluid conduit, comprising a main port, a working fluid passage and a working fluid port, and a port to apply the vacuum, the cannula can include a sensor port to allow sensing pressure or other characteristics of the working fluid at a point closely adjacent to the connection between the cannula and the biological system.

Abstract: This invention provides improved means for displaying and preserving specimens of various kinds, such as flower blossoms. The medium for encapsulating the specimen is a resin material which, when fully cured, is soft and pliable, having a cone penetration value of about 80 to about 400 (10-.sup.1 mm) (ASTM D217-68 or D1403-69) and an ultimate elongation of at least about 100% (ASTM D638-80 or D412). This invention also provides a system for collecting specimens, preserving and dehydrating them, and transporting them to another site where the specimens are encapsulated in the soft, pliable resin for final preservation and display.