Abstract: A dc power supply for spacecraft arcjet thrusters has an integral automatic starting circuit and an output averaging inductor. The output averaging inductor, in series with the load, provides instantaneous current control, and ignition pulse and an isolated signal proportional to the arc voltage. A pulse width modulated converter, close loop configured, is also incorporated to give fast response output current control.

Abstract: A method is provided to bond strain gauges 6 to various materials. First, a tape 9 with an adhesive backing 10 is placed across the inside of fixture frame 8. Strain gauge 6 is flatly placed against adhesive backing 10 and coated with a thin, uniform layer of adhesive 5. Tape 9 is then removed from fixture frame 8 and placed, strain gauge side down, on the material to be tested. If the material is a high reluctance material 12, induction heating source 20 is placed upon tape 9. If the material is a low reluctance material 13, a plate 23 with a ferric side 21 and a rubber side 22 is placed, ferric side down, onto tape 9. Induction heating source 20 is then placed upon rubber side 22. If the material is an insulator material 14, a ferric plate 7 is placed on tape 9. Induction heating source 20 is then placed on ferric plate 7.

Abstract: A wick for use in a capillary loop pump heat pipe. The wick material is an essentially uniformly porous, permeable, open-cell, polyethylene thermoplastic foam having an ultra high average molecular weight of from approximately 1,000,000 to 5,000,000, and an average pore size of about 10 to 12 microns. A representative material having these characteristics is POREX UF which has an average molecular weight of about 3,000,000. This material is fully compatible with the FREONs and anhydrous ammonia and allows for the use of these very efficient working fluids in capillary loops.

Abstract: For use with plasma arc welding apparatus, a control system is set forth. The plasma arc welding apparatus includes a plasma arc power supply (12), a contactor (20), and an electrode assembly for moving the electrode (32) relative to a work piece (22). The electrode assembly is raised or lowered by a drive motor (24). The present apparatus includes plasma arc adapter (48) connected across the power supply to measure the voltage across the plasma arc. The plasma arc adapter forms a DC output signal input to a differential amplifier (60). A second input (58) is defined by an adjustable resistor (56) connected to a DC voltage supply to enable operator control. The differential amplifier forms an output difference signal provided to an adder circuit (64). The adder circuit then connects with a power amplifier (68) which forms the driving signal for the motor.

Abstract: An ice detector 11 is provided for the determination of the thickness of ice 22 on the outer surface 12 on an object (e.g., aircraft 10) independently of temperature or the composition of the ice 22. First capacitive gauge 16, second capacitive gauge 18, and temperature gauge 20 are embedded in embedding material 14 located within a hollowed out portion of outer surface 12. This embedding material 14 is flushed with outer surface 12 to prevent undesirable drag. First capacitive gauge 16, second capacitive gauge 18, and temperature gauge 20 are respectively connected to first capacitance measuring circuit 24, second capacitance measuring circuit 26, and temperature measuring circuit 28. The geometry of first and second capacitive gauges 16 and 18 is such that the ratio of the voltage outputs of first and second capacitance measuring circuits 24 and 26 is proportional to the thickness of ice 22, regardless of ice temperature or composition. This ratio is determined by offset and dividing circuit 29.

Abstract: A semiconductor thermocouple unit is provided for improving heating and cooling of memory metal actuators. The semiconductor thermocouple unit is mounted adjacent to a memory metal actuator and has a heat sink connected thereto. A flexible thermally conductive element extends between the semiconductor thermocouple and the actuator and serves as a heat transfer medium during heating and cooling operations.

Abstract: A method and apparatus to measure the thickness of liquid 12 on a surface 14 independent of liquid conductivity. Two pairs of round, corrosion resistant wires, 18 and 20, are mounted in an insulating material 16 such that the cross-sectional area of each wire is flush with and normal to the surface 14. The resistance between each pair of wires 18 and 20 is measured using two AC resistance measuring circuits 22 and 24 wherein the ratio of the outputs of the two resistance measuring circuits is indicative of the thickness of the liquid 12 on the surface 14.

Abstract: A foldable expandable pallet (10) having a basic square configuration. Each pallet is comprised of a plurality of struts (11, 13) joined together by node point fittings (12) to make a rigid structure. Some of the struts have hinge fittings (15) and are spring loaded to permit collapse of the module for stowage (26) and transport to a space station. Dimensions of the pallet are selected to provide convenient, closely spaced attachment points between the relatively widely spaced trusses (21, 30, 31) of a space station platform. A pallet is attached to a truss at four points: one close fitting hole (22); two oversize holes (24, 25); and a slot (23); to allow for thermal expansion/contraction and for manufacturing tolerances. Applications of the pallet include its use in rotary or angular joints (29); servicing of splints; with gridded plates (34); as instrument mounting bases; and as a roadbed (36) for a Mobile Service Center (MSC) (37).

Abstract: A digital logic controller providing instruction execution times on the order of 50 nanoseconds and employing a read-only memory outputting instructions to a pipeline register, a portion of each instruction providing a status-select control signal and address signals for controlling selection of the next instruction from the read-only memory.

Abstract: A disc brake system for a shuttle orbiter including an annular disc element (10) having internal radially directed and angularly spaced relief slots (12) and trapezoidial shaped carbon pad members (15) disposed circumferentially around the disc element. T Clips (19, 19') snugly engage the outer ends of the pad members and are attached to rivet heads (34, 35) and (34', 35') and have guide members (51, 51') slidably received in guide grooves (50, 50') in a spring housing (20). Springs (61) provide a force tending to move the T Clips toward the center of the disc where the magnitude of the force can be adjusted by a screw (65).

Abstract: A lock joint for a space station truss has a plurality of struts (2-5) joined together in a predetermined configuration by node point fittings (1). The fittings have removable inserts (6) therein. The lock joint has an elongated housing (12) connected at one end to a strut. A split-fingered collet (53) is mounted within the housing for movement reciprocably therein. A handle (25) on the housing is connected to the collet for moving the collet into the insert where the fingers of the collet expand to lock the joint to the fitting.

Abstract: A suitable member formed from sintered, powdered, stainless steel is contacted with a nitrate solution of a soluble alkali metal nitrate and a metal such as zirconium in a pH range and for a time sufficient to effect the formation of a membrane of zirconium oxide on the stainless steel support, the membrane preferably including an organic polymeric material such as polyacrylic acid.

Abstract: A high effectiveness contour matching contact heat exchanger (10) includes two opposing plates (12,13), each having alternating double rows (25) of attached pins (20). The ends (23) of the pins (20) opposite their respective plates (12,13) are received in tight-fitting holes (40) in the opposite plate (12,13), providing for flexibility of the heat exchanger (10) to maintain efficient thermal transfer contact between the plates (12,13) and the external thermal sources (50,51) of heat or cold, without causing gaps between the ends (23) of the pins (20) and their respective opposite plates (12,13) that decrease heat transfer effectiveness by adversely affecting flow distribution of the fluid flowing therepast.

Abstract: A method and device 15 is provided for a quick, accurate and on-line determination of heats of combustion of gaseous hydrocarbons. First, the amount of oxygen in the carrier stream air is sensed by oxygen sensing system 20. Second, three individual volumetric flow rates of oxygen, carrier stream air, and hydrocarbon test gas are introduced into burner 19. The hydrocarbon test gas is fed into burner 19 at a volumetric flow rate n measured by flowmeter 18. Third, the amount of oxygen in the resulting combustion products is sensed by oxygen sensing system 20. Fourth, the volumetric flow rate of oxygen is adjusted until the amount of oxygen in the combustion product equals the amount of oxygen previously sensed in the carrier stream air. This equalizing volumetric flow rate is m and is measured by flowmeter 16. The heat of combustion of the hydrocarbon test gas is then determined from the ratio m/n.

Abstract: Synthetic procedures to tetraalkyls, tetraacids and dianhydrides substituted 1,1,1-triaryl-2,2,2-trifluoroethanes which comprises: (1) 1,1-bis(dialkylaryl)-1-aryl-2,2,2-trifluoroethane, (2) 1,1-bis(dicarboxyaryl)-1-aryl-2,2,2-trifluoroethane or (3) cyclic dianhydride or diamine of 1,1-bis(dialkylaryl)-1-aryl-2,2,2-trifluoroethanes. The synthesis of (1) is accomplished by the condensation reaction of an aryltrifluoromethyl ketone with a dialkylaryl compound. The synthesis of (2) is accomplished by oxidation of (1). The synthesis dianhydride of (3) is accomplished by the conversion of (2) to its corresponding cyclic dianhydride. The synthesis of the diamine is accomplished by the similar reaction of an aryltrifluoromethyl ketone with aniline or alkyl substituted or disubstituted anilines. Also, other derivatives of the above are formed by nucleophilic displacement reactions.

Abstract: A mobile platform (B) for transit about a working face (51) of a truss. The truss has a grid of node guide pins (54) having stationary sprockets (54D). The platform (B) has a rail system (52) comprised of transversely disposed T-shaped tracks (60), direction changing means (58) at their intersections and retractable, reversible chain drive systems (22). The chain drive (22) selectively engages the sprockets (54D) of the guide pins (54) providing selective movement of the platform (B) in two orthogonal directions (L and T). The present invention provides a near-uniform traversing velocity with minimal dynamic loading on the system. Pivoting changers (C1 and C2) move the platform (B) from one face (51) to another.

Abstract: A microwave oscillator is provided which can operate at a temperature of many degrees above absolute zero while providing very low phase noise that has heretofore generally required temperatures within a few degrees K. The oscillator includes a ring-shaped resonator element of ruby (sapphire plus chromium) or iron sapphire crystal, lying adjacent to a resonator element of sapphire, so the regenerator element lies directly in the magnetic field of the resonator element. The resonator element is substantially devoid of contact with electrically conductive material. Microwave energy of a pump frequency (e.g. 31GHz) is applied to the regenerator element, while signal energy (e.g. 10GHz) is outputted from the resonator element.

Abstract: The invention relates to a clamping device used for making up or breaking apart joints of drill pipe, drill collars and the like in mouse hole pipe during oil drilling operation. A clamping means of the device firstly clamps the drill pipe therebetween during its moving down and centripetally simultaneously by the self-weight of drill pipe to be clamped, then tightly clamps the drill pipe with a force generated by rollers' moving inwardly to the center of the device along the concavity of the turning plate with the rotation of a kelly. It can be used instead of a back tong when making-up joint in mouse hole pipe with a tong.

Abstract: A signal is transmitted from a first location to a remote second location where a target carrying a transponder is positioned. The transponder re-radiates the signal to the first location where it is received. A phase comparator generates from the transmitted and received signals a measurement of their phase difference which is functionally related to the distance between the first and second locations. In one embodiment, the transponder is a passive parametric oscillator, being powered by energy received from the transmitted signal, which generates and transmits a subharmonic of the transmitted signal.

Abstract: A moving wall, continuous flow electrophoresis apparatus (10) having a frame (18) with an electrophoresis chamber (12) mounted between a pair of synchronously driven belt walls (14, 16). The frame (18), and thus the chamber (12), is supported between the belt walls (14, 16) and is angularly positionable with respect to the direction of belt travel. The belts are stored on supply reels (98, 156) at one end of the device and are taken up on driven reels (94, 132) at the other end, thus constantly exposing new belt material within the chamber.