Abstract: A reconfigurable grading blade attachment for a work machine includes an attachment frame, a pivot beam extending transversely to the frame length, a left stabilizer wheel assembly pivotally coupled to the left portion of the pivot beam, a right stabilizer wheel assembly pivotally coupled to a right portion of the pivot beam, a center mount, a left hydraulic actuator pivotally coupled to the left portion of the pivot beam, a right hydraulic actuator pivotally coupled to the right portion of the pivot beam, and a grading blade extending transversely to the length of the work machine frame. Retraction of the left hydraulic actuator rotates the left stabilizer wheel assembly upwards about the left wheel lift axis. Retraction of the right hydraulic actuator rotates the right stabilizer wheel assembly upwards about the right wheel lift axis.

Abstract: A box blade grading attachment of the present disclosure may comprise an attachment frame, a coupler bracket, a tilt connection, a pivot beam, left and right caster wheels, a grading box, and a tilting actuator. The attachment frame includes a rear attachment frame portion for coupling of the box blade grading attachment to a construction machine and an upper attachment frame portion having an upward facing reference surface. The tilt connection defines a tilt axis about which the attachment frame may tilt relative to the coupler bracket. The tilt axis may be substantially parallel to the upward facing reference surface. The pivot beam is pivotally connected to the upper attachment frame portion and includes left and right caster wheels pivotally connected to the pivot beam. The tilting actuator tilts the attachment frame and the grading box about the tilt axis relative to the coupler bracket.

Abstract: An arcjet thruster is disclosed which has an electrically conductive anode body having an anode cavity therein which defines a nozzle symmetrical about a central axis. The anode cavity has a tandemly arranged divergent recombination portion and a divergent expansion portion. The expansion portion has a greater rate of divergence than the recombination portion. The anode body further preferably comprises a cylindrical constrictor portion upstream and in tandem with the recombination portion. An electrically conductive cylindrical cathode body is coaxially arranged and spaced from the anode body by a gap. An electrical current source connected to the cathode and the anode produces an electrical arc across the gap. A vortex flow of propellant gas is fed through the gap and through the nozzle to produce thrust. The vortex flow of propellant gas pushes the arc through the constrictor into one of the divergent portions of the nozzle.

Abstract: An arcjet thruster has a body defining a constrictor and nozzle constituting an anode and forming an arc chamber. An elongated rod constitutes a cathode spaced from the constrictor by a gap generally coextensive with the arc chamber. An electrical potential is applied to the anode and cathode to generate an electrical arc in the arc chamber from the cathode to the anode. Propellant is supplied to the arc chamber with generation of the arc so as to produce thermal heating and expansion of the propellant through the nozzle. The thruster employs several features which improve its performance. One feature relates to the use of propellant blends with high specific impulse additives. Another feature relates to injection of the high specific impulse additive into the bulk propellant feed at the region of the cathode tip.

Abstract: An arcjet thruster has a body defining a constrictor and nozzle constituting an anode and forming an arc chamber. An elongated rod constitutes a cathode spaced from the constrictor by a gap generally coextensive with the arc chamber. An electrical potential is applied to the anode and cathode to generate an electrical arc in the arc chamber from the cathode to the anode. Propellant is supplied to the arc chamber with generation of the arc so as to produce thermal heating and expansion of the propellant through the nozzle. The thruster employs several features which improve its performance. One feature relates to the use of propellant blends with high specific impulse additives. Another feature relates to injection of the high specific impulse additive into the bulk propellant feed at the region of the cathode tip.

Abstract: An arcjet thruster has an anode body forming a constrictor and a nozzle which define an arc chamber. The thruster also has a cathode in the form of a rod having a tip and being spaced upstream from the constrictor. The thruster employs several features which reduce anode and cathode erosion and increase the operational life of the thruster. One set of features relate to the employment of cathode and anode shaping. Another feature relates to the use of a propellant injector having a series of radially and tangentially arranged passages for providing direct injection of propellant gas into the arc chamber and enhanced convective cooling of the anode.