Abstract: A washer for use with a bone screw having a shank and a head defining a maximum diameter, includes a body having a bottom face for engaging the surface of a bone and an opening therethrough sized to receive the shank of a bone screw extending therethrough. The washer includes a cavity in communication with the opening at the bottom face and configured to receive the head of the bone screw when the shank extends through the opening at said bottom face. The washer includes a plurality of flaps distributed around the opening of the cavity that are bendable from a first configuration in which the flaps define an opening sized to receive the head of the bone screw, to a second configuration in which the flaps define an opening smaller than the maximum diameter of the head of the bone screw.

Abstract: The present invention relates to a genotype-independent method for transforming and selecting plant explants. The transformation method includes pre-culturing the explants in the presence of an Agrobacterium inducer and exposing the transformed explants to a shoot regeneration media that accelerates shoot development. Plants generated from this transformation method are provided. In particular, methods for obtaining transgenic Eucalyptus and pine cells and regenerating stably transformed Eucalyptus and pine trees are provided. The invention also provides media, methods, and plasmids for selecting and regenerating plants, particularly forest trees.

Abstract: An intermediate thrust bearing is positioned between the rotating cutters and its bearing pin of an earth-boring bit. The intermediate bearing is so configured to take outthrust loads, without rotation, that are directed axially against a radially disposed surface of the roller cone journal as the rock bit works in a borehole.

Abstract: A method to retain a nozzle in a rock bit is disclosed for use particularly with air-type roller cone rock bits. A plastic nozzle body is formed with a multiplicity of radially disposed fins equidistantly spaced on the periphery of the nozzle body. A nozzle retention hole is formed in the body of the rock bit with a diameter slightly less than the diameter of the fins on the plastic nozzle. As the plastic nozzle body is forced into the nozzle retention hole, the fins deflect slightly in a downstream direction and "bite" against the nozzle retention walls formed by the bit body.

Abstract: A method by which a previously molded hollow plastic retainer having an open end portion necessitated by the need to withdraw a mold core therefrom may be embedded in a molded trim article with the open end beneath the surface and yet the molding material is prevented from flowing through the open end portion and filling the hollow of the retainer.

Abstract: The bearing surface of a cone cutter bit is hard-faced by forming a substantially cylindrical bearing structure on the drill bit leg having a diameter less than that of the mating bearing on said cone cutter. A cylindrical tubular sleeve of hard low friction metal which has an inner diameter greater than the diameter of said cylindrical bearing structure is inserted over said bearing structure, and a disc is placed over the end and inside said tubular metal sleeve. Solder is flowed between the sleeve and the disc to attach the sleeve and disc to the bearing structure to create a hard-faced bearing. Openings can be preformed in the sleeve or disc to match fluid cooling holes in the drill bit leg.

Abstract: This technique for manufacturing a rotary rock bit involves forming a rock bit leg segment having an upper pin end and a lower shirttail end including a socket having a semi-cylindrical faying surface transverse to the axis of the rock bit being formed. A separately formed journal insert includes a journal pin for mounting a rock bit cutter cone and a shirttail portion transverse to the axis of the journal pin. The insert has a semi-cylindrical faying surface on the shirttail portion coaxial with the journal pin. The insert is fitted into the rock bit leg segment with the semi-cylindrical faying surface on the insert mated with the semi-cylindrical socket surface on the bit leg segment. The semi-cylindrical faying surfaces are then electron beam welded. A cutter cone is assembled on the journal pin and three such rock bit leg assemblies are welded together to form a rock bit which is completed with conventional machining operations.

Abstract: A rotary air percussion bit has a cylindrically shaped sidewall, a body portion with a flat or recessed face on one end and a shank attached to the remaining end. A plurality of inserts of wear resistant material is mounted in the face and extending outwardly therefrom. A plurality of chip cutting grooves is formed in the face and extending radially from the axis of the body outwardly to the sidewalls. In order to improve the chip removal from the bit a plurality of chip clearance grooves is formed in the sidewall of the body extending from the terminus of the face chip cutting grooves and spiraling from the face to the shank end. The angle of the spiral with respect to the face is less than 45.degree..