Abstract:
A removable cover for a shipboard lashing socket that provides a generally cruciform access opening flush with the deck. The cover has a plate which totally covers the cruciform opening and the underside of which has a locator that fits into one leg of the opening and prevents rotation. A central housing portion on the underside of the plate has opposed, horizontal bores each containing a rotatable ball detent, a retainer, a ball seat and a spring biasing the seat and ball detent to its protruding position. The ball detents in an installed cover latchingly engage the lower edge of the flush deck portion of the socket between adjacent legs of the cruciform opening.
Abstract:
A method for lubricating surfaces subject to cycles of high-low temperature conditions by electro-deposition of a solid film lubricant having strong chemical bonds with the substrate surface, the lubricant containing gold and a refractory metal and oxides thereof, the film lubricant being deposited from an aqueous solution of a potassium gold cyanide consisting essentially of 5 to 15 grams per liter potassium gold cyanide, a highly ionizable refractory metal compound the metal constituent of which is selected from the group consisting of molybdenum, rhenium, ruthenium and tungsten, the quantity of metal compound at or exceeding 5 grams per liter, and the solution containing a nonreducible conducting salt of up to about 150 grams per liter, deposition being at a solution temperature of 140*F to to 160*F and a controlled solution voltage of 1.4 to 2.0 volts versus a saturated calomel electrode, the solution and deposition being controlled so that the solid lubricating film deposited has a concentration of about 2% to 50% by weight of the refractory metal oxides, the remainder being essentially gold and said refractory metal.
Abstract:
A drifting ocean buoy is described which utilizes a drag structure which follows the water mass of the ocean as it flows in the form of the ocean current, and which also has an aerodynamically shaped low wind drag mast to minimize wind induced errors in ocean current drift measurements; the drag structure also being stable and resistant to heaving (pitch and roll) so as to maintain a mast carried antenna above the water even at high sea states.
Abstract:
An electronic navigation system is disclosed having a range calculation unit including a velocity detector which provides an error signal having a sense and magnitude corresponding to the sense and magnitude of reply pulses which are received during transceiving operations. The calculation unit also includes a counter system for up-down counting of reply pulses which indicates the quantity of valid reply pulses which have been received.
Abstract:
A digital frequency synthesizer is described which employs an accumulator to determine the number of cycles of a reference frequency source which is divisible into the period of the frequency to be generated and to determine a digital number which is related to the remainder or the fractional cycle of the reference frequency required to complete the period of the generated frequency. A digital/analog interpolator translates this digital number into a fractional period and combines it with the integral determined by the accumulator division and outputs a pulse train having the combined period of the frequency to be synthesized.
Abstract:
A device for locating a pilot hole and aligning it with the operating mechanism of an automatic riveting machine is disclosed. Automatic riveting machines typically position a pilot hole in the workpiece to be riveted, drill an appropriate hole, countersink one or both external surfaces, insert a rivet, then press to deform the rivet. The disclosed hole locator includes a pin movable into alignment with the metal working axis, which is the line along which the drilling, countersinking, rivet pressing, etc., tools move. The pin is moved into the pilot hole to align the pilot hole with the riveting machine. The machine is operated to clamp the workpiece with the pin still in position. Then the pin is withdrawn and the riveting cycle completed. This hole locator can also be advantageously used with drill presses or other similar devices.
Abstract:
A millimeter wave oscillator has a case of block construction defining a waveguide passageway with a waveguide flange at the output end integral with the case. A plunger with a half-round surface facing the open end is disposed adjacent a wafer-like disc and a source diode has a terminal which is contacted by the disc. The diode is adjustably disposed in the case. The disc is disposed on the end of a piston slideably disposed in a capacitor body which is coupled to a source of DC bias. A spring in the body urges the disc into contact with the diode. Stubs are provided for impedance matching of the following circuit.
Abstract:
A ship for the transporation of liquified gases at pressures approximately equal to atmospheric pressure and at temperatures substantially below ambient temperature has a double-hull structure with both the inner and outer portions of the hull made from an aluminum alloy having high strength and ductility at cryogenic temperatures. A layer of insulation is provided on the interior wall of the inner hull for thermally insulating the liquid gas cargo from the ambient temperature. A layer of an impermeable material, preferably in the form of a laminate, is disposed on the interior surface of the insulation layer to prevent gas/liquid leaks.
Abstract:
A method and apparatus for the detection of incipient structural failures by acoustic emission monitoring in the presence of background noise. One or more ''''master'''' sensors are placed on the structure to be tested and are surrounded by a plurality of ''''slave'''' sensors. Each sensor detects acoustic emissions in the structure and sends a corresponding signal to an Acoustic Emission Monitor (AEM). The AEM includes electronic circuitry which accepts only signals which reach the master sensors before they reach the slave sensors, thus excluding signals originating outside the area covered by the sensor array. The AEM also contains frequency filters excluding signals outside the desired frequency range, to exclude most background ''''noise.'''' These techniques permit the detection of acoustic emissions from flaws and propagating cracks in structures of complex shape in an acoustically noisy environment.