Abstract: The present invention is directed to an apparatus and method for actuating a valve. The present invention is particularly useful with a valve for imparting pressure pulses in a pressure pulse telemetry system. The present invention relates to an apparatus and method for actuating a valve from a first to a second position wherein the actuating force is adjusted in response to a measured value characteristic of the minimum force necessary to actuate the valve. The apparatus and method of the present invention advantageously and beneficially reduces the power requirement for actuating the valve, prolonging battery life, and minimizes the deleterious affects of excess mechanical and electrical energy on the valve and circuit components, prolonging valve and circuit life.

Abstract: A first sweep signal consists of a plurality of waveforms having non-invariant fundamental periods exhibiting a monotonic frequency progression of at least one octave over the duration of the sweep. Each waveform may consist of an ordered set of asymmetrical pulses distributed within the period of the waveform in a prescribed sequence as a function of time. A second sweep signal is orthogonalized with respect to the first by time-reversing the distribution-sequence of the pulse set.

Abstract: For use in an acoustic logging tool, an apparatus which digitizes simultaneously obtained acoustic signals is set forth in the preferred and illustrated embodiment. The device cooperates with N acoustic receivers in a sonde. After an acoustic pulse is transmitted, data is observed at all N acoustic receivers. This apparatus comprises a multiplexer which is connected to the several receivers. The several input signals are multiplexed, thereafter input to a digital data converter forming a procession of output digital words, and the words are stored in a selected order in a digital data buffer. They are delivered to the surface through a telemetry transmitter at a slower rate than the rate at which the data is created. In addition, a transmitter monitor is included. This provides a signal alternately digitized for a specified interval to enable coordination of the data reduction from the acoustic receivers in contrast with the timing of the transmitted acoustic pulse.

Abstract: A rail gun barrel includes gas containment means for limiting the penetration of high pressure gas into interfaces between rails and insulating members. The preferred gas containment means comprises one or more channels formed in one or more of the interfaces. In one embodiment of the invention, the channels simply provide space for expansion of gas. In another embodiment, the channels are partially or totally filled with seal material which prevents gas from escaping radially outward beyond the channels.

Abstract: A rail gun barrel includes a pair of insulators which are axially prestressed in compression.

Abstract: The electromagnetic projectile launching systems of this invention accelerate projectiles by switching current from a current source to a pair of conductive projectile launching rails such that current flows through the rails and through an armature between the rails to produce an accelerating force on a projectile and the rate of current injection into the rails is controlled so that the initial projectile acceleration occurs at a reduced current level compared to the current used for subsequent projectile acceleration. This reduced current level is provided by initially shorting a resistor connected between one of the rails and the power source or alternatively by inserting a resistor in series with a switch which partially commutates current from the current source to the projectile launching rails. The maximum rail surface temperature during a launch is reduced by controlling the rate of initial current injection.

Abstract: An internally augmented, parallel rail electromagnetic projectile launching system includes a plurality of projectile launching rail pairs wherein the stacked height of the rails adjacent to the launcher bore decreases from the breech end to the muzzle end of the launcher. The launcher rail pairs may be electrically connected in series with each other and in series with an external current source. Alternatively, a separate though not necessarily entirely independent current source may be provided for each pair of rails and switching means may be included to substantially simultaneously connect each current source to its associated rail pair.

Abstract: A vibratory seismic surface source includes a single vibrating mass, the energy of which is coupled with the earth through a ground contacting base plate. The vibrating mass is connected to the base plate by means of a ball and socket joint which constitutes a universal pivot for the vibratory axis of the mass. Thus, this vibratory axis may be made to assume any vector path with respect to a seismic line. In this manner, any desired combination of compressional and shear waves, both SH and V type, may be generated and recorded simultaneously at a point on the earth's surface remote from the source.

Abstract: An equipoised lamp is provided which comprises a lamp head mounted on an adjustable arm assembly which is counter-balanced by internal coaxial torsion springs mounted within the adjacent end sections of the arms. The end sections are bent at 90.degree., so that the arms may be set to desired angular positions about respective mutually perpendicular axes. The arms may be mounted on an upright base so that the assembly constitutes a floor lamp, or they can be clamped to a table, to provide a draftsman's lamp assembly, and the like. The lamp head itself is mounted at an intermediate position on one of the arms, so that the end of that arm may form a handle for manually adjusting the lamp head to any desired position without any need to touch the hot lamp.

Abstract: An armature for use in electromagnetic projectile launchers is provided with a plurality of modular conductive fiber bundles which are arranged in a rectangular array and attached to an insulating armature support structure. The conductive fibers extend across the launcher bore and are sized to provide an interference fit between a pair of generally parallel conductive launcher rails. Each fiber bundle includes a rectangular central sheath and a pair of peripheral rectangular sheets positioned on opposite sides of the central sheath. The axis of each peripheral sheet is positioned at an angle with respect to the axis of the central sheath.

Abstract: An improved electromagnetic induction method and apparatus therefor for simultaneously collapsing and propelling a deformable annular-shaped workpiece of relatively lightweight construction in a direction outwardly of the apparatus and along its axis wherein the apparatus is made up of seven different embodiments for carrying out the method. Each apparatus is generally comprised of a framework. The framework includes at least one pulse coil means; and a power supply circuit is connected to the pulse coil means. Annular-shaped surface portions of various embodiments of the apparatus define part of an aperture or passageway for receiving a workpiece and function to position the workpiece in mutual inductance relation to the coil means.

Abstract: The invention is a multi-port, multi-chamber, tuned, air-powered subsea seismic source. It is suitable for producing a seismic wave in a subsea environment during seismic prospecting. Interconnected pressurized chambers are formed between plates located on a movable shuttle and cylinder walls extending inward from the source housing. The source is fired by moving the shuttle through a stroke and allowing the pressurized air within the air chambers to exit through ports into the surrounding water. A unique seal arrangement in also shown.

Abstract: A barrel assembly for an electromagnetic rail gun is strong enough to withstand bursting forces generated during firing of the gun and has cooling capacity sufficient to enable the barrel to be fired repeatedly without overheating. The barrel includes a pair of elongated, generally parallel conductive rails having radially outwardly extending fins for structural support and heat transfer.

Abstract: Improved gun-firing system for electrically augmenting the energy released y ignited propellant of the system so as to increase the velocity of the projectile as it launches from the system thereby increasing the probability that it will strike a fast-moving target. The system is generally made up of a barrel and a breech. The breech is provided with a firing chamber for receiving a projectile and an ignitable propellant. In one embodiment, the breech of the system is generally comprised of a detonator, a pair of relatively spaced pressure-responsive switches and a helically wound electromagnetic coil. A power supply is connected by an interlock to the switches and coil such that the coil is not energized until both switches close. These switches close in response to the pressure of the plasma that has been progressively formed from igniting the propellant in the breech chamber.

Abstract: An oil mist generator for generating an oil mist for lubrication purposes wherein the oil reservoir is heated by passing a heated air conduit through the body of oil to heat the oil and therefore mixing heated oil and heated air in a mist generator.

Abstract: The invention relates to a compact tunable subsea seismic source. The source has multiple seismic radiating plates placed symmetrically about a central housing which contains a hydraulic actuating system. The source is towed to optimize the amount of energy applied to the surrounding water.

Abstract: A dual-mode vibrator for alternately injecting P-waves and S-waves in the earth including a hydraulically driven shaker assembly, a ground-contacting base plate, and a jacking means for raising and lowering the base plate relative to a vehicle. The shaker assembly is supported above, and coupled to the base plate by a supporting means. The supporting means has a first configuration for coupling the shaker assembly to the base plate for generating P-waves and a second configuration for pivotally coupling the shaker assembly to the base plate and to a rigid member associated with the vehicle for injecting S-waves.

Abstract: An electromagnetic rail gun system includes an electromagnetic rail gun, a power supply, a cartridge and breech means for holding the cartridge. The gun includes a breech end and a muzzle end and a pair of substantially parallel rails defining a bore for receiving a projectile. The cartridge has releasably held projectile having a nose and a trailing end carrying an armature. The cartridge also includes a casing comprising a pair of electrically conductive casing segments spaced by insulation. The system further comprises interconnection means from the power supply connecting the breech end of the rails in parallel with the casing segments of a cartridge held in the breech means. The cartridge further includes shunt means interconnecting the casing segments for carrying current therebetween, and the armature is in electrically conductive relationship with the casing segments.

Abstract: A rail gun barrel assembly includes barrel components which are radially constrained by a pressure medium contained within a lightweight outer shell.

Abstract: A switch for use in an inductive energy store transfer circuit utilizes a quantity of electrically conductive liquid bidirectionally flowable between a position that establishes electrical connection between electrodes and a position that opens electrical connection between the electrodes. High pressure gas biases the liquid to a position that establishes electrical connection between the electrodes, and yieldably resists movement of the liquid toward the position that opens electrical connection between the electrodes. Current through the switch electrodes produces a magnetic force that acts on the liquid and urges it toward the position that opens electrical connection between the electrodes. Switching action occurs upon a predetermined magnitude of current being attained.