Abstract: An accelerometer without internal mechanical attachments. Three parallel cylindrical magnets are fixed within a housing. Each cylindrical magnet has a long axis extending through the housing and a cylindrical cross-section. The cylindrical cross-sections of the cylindrical magnets are organized to form a triangular formation. The magnetization of the cylindrical magnets is tangential to the triangular formation. A diamagnetic mass object levitates within the three cylindrical magnets by the magnetization of the cylindrical magnets at an equilibrium position near the center of the triangular formation and near a central axis of the three parallel cylindrical magnets when no external force is applied. Sensors detect the location of the diamagnetic mass object when the diamagnetic mass object is displaced from the equilibrium position near the center of the triangular formation and the three parallel cylindrical magnets by an external force to the housing.

Abstract: A pneumatic vibration isolating suspension is disclosed for supporting a payload on a moving carrier while suppressing the transmission of vibrations in the 1 to 50 Hz band between the carrier and the payload. The disclosed invention can be deployed in the air in a towed carrier or sonde, and operated from aircraft power, making it a suitable platform for airborne geophysical instrumentation. It also has particular application to airborne electromagnetic surveying operating in the same frequency band because the sensor vibrations that result in noise created by the modulation of the sensor coupling with the earth's magnetic field are suppressed. Furthermore, the invention can be constructed from resistive composite materials and non-magnetic metals, so it can be operated without producing significant modification to the ambient electromagnetic field being measured.

Abstract: A blade setting tool for calibrating the mounting position of a reciprocating blade in an electric trimmer after the blade has been removed for cleaning or sharpening. The blade setting tool provides a time-saving and convenient method for mounting of the reciprocating blade such that a pre-determined clearance is maintained between the reciprocating blade and the stationary blade to avoid cutting or biting problems during a hair cut.

Abstract: A hand-held system for determining the slope of an element having an irregular surface, such as a shingled roof, or along a surface that is partially obscured by adjacent elements. The system comprises an inclinometer having a double indicator to provide two simultaneous readings of slope.

Abstract: A laser plumb includes a laser, and a mass that is rotatable about a spin axis to stabilize the laser. The mass is mounted to a support to be pivotable about at least one axis, and preferably two axes. The two axes are perpendicular to each other and the spin axis. The laser is mounted to the mass to maintain its orientation relative to the support, as the mass rotates about the spin axis. A weight below the tilt axes aligns the spin axis with the gravitational axis. Preferably, the mass and laser are mounted to the support by a gimballed mount. The plumb optionally includes markings on its base to measure a deflection of the laser from the support, thereby allowing measurement of the angle of inclination of a surface supporting the base.

Abstract: A calculation system for calculating the control signals which are designed to perform a frequency-dependent weighting of the angular velocity signals and the angular position signals. The angular velocity indicators are preferably used for stabilization in a high frequency band while the angular position indicators are suitable for stabilization in a low frequency band. A further calculation system which is designed to perform the frequency-dependent weighting such that the control signals for frequencies below a certain frequency are substantially determined by the angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

Abstract: A calculation system for calculating the control signals which are designed to perform a frequency-dependent weighting of the angular velocity signals and the angular position signals. The angular velocity indicators are preferably used for stabilization in a high frequency band while the angular position indicators are suitable for stabilization in a low frequency band. A further calculation system which is designed to perform the frequency-dependent weighting such that the control signals for frequencies below a certain frequency are substantially determined by the angular position signals and the control signals for higher frequencies are substantially determined by the angular velocity signals.

Abstract: A means for damping a low-friction azimuth resolver by use of an array of small magnets acting on a metallic pendulum attached to the resolver shaft. The magnetic field acts on the pendulum motion to induce a motional electromotive force and associated currents, which produce forces opposed to the motion, thereby acting as a non-contact damper on the resolver shaft. When the resolver shaft is at rest, no "eddy currents" are produced in the static magnetic field and no damping force exists. If the shaft moves, the attached pendulum cuts the magnetic flux lines and produces a drag force proportional to the shaft angular speed. The pendulum is typically made of diamagnetic material, such as lead or copper, thereby assuring that the induced forces arise solely from the motion. The magnetic field is produced by an array of small, but intense, samarium-cobalt magnets contained in a compact package providing for uniform damping throughout 360.degree. of resolver motion.

Abstract: In an apparatus for making at least one linear measurement, elongated flexure members are positioned to have a movable end move corresponding to the linear dimension being measured. The flexure members are the type utilizing a pair of parallel beams so as to obtain parallel motion and obtain an accurate measurement of the movable end.

Abstract: An inclinometer comprises a casing, a pendulum mounted in the casing and having a pendulum swing axis, a mass in the form of a flywheel mounted in the casing and which tends to remain stationary when the casing is rotated about the pendulum swing axis, and a damping means coupling the pendulum to the flywheel.

Abstract: A displacement transducer for accurately detecting both linear and angular displacements and velocities, between objects moving relative to one another. The displacement transducer is structured to accurately operate under large gravitational accelerations and vibration extremes as well as minimize the adverse effects of environmental degradation upon the displacement transducer's performance.

Abstract: A chamber filled with an oscillation damping liquid has a non-magnetic plumb bob suspended from an upper portion of the chamber and a radiated beam path traverses the chamber below the suspension point of the freely suspended plumb bob. The beam path and plumb bob are arranged in a desired relationship whereby in order for the suspending member of the plumb bob to completely block the beam path the chamber, or the body on which it is mounted, must be in a desired predetermined position, such as a true horizontal or a true vertical position. An electric power source and circuitry is provided to operate in response to blocking of the beam path to provide a desired electrical output indicating the desired predetermined position has been achieved and is being maintained. The electrical output may be used to operate visual or aural indication emitting device to notify the user when the desired position is achieved.

Abstract: An angular orientation detector and indicator has a plumb bob suspended in a vertically extending chamber of a housing. A beam of radiation is emitted across the chamber from a beam emitter to a beam receiver and the plumb bob is swingable through a beam path extending between the emitter and receiver. When the housing of the detector is positioned in a preselected angular orientation the plumb bob comes to rest blocking the beam path to substantially reduce or prevent the radiated beam from being received by the receiver. An electrically actuated signal, such as an audible or visual signal, or both, is thereby actuated to indicate that the detector is at a preselected angular orientation. Such detectors may be mounted on builder's levels to indicate when the level is in a preselected angular orientation, such as a horizontal or vertical orientation. Other embodiments and useful applications of such detectors are also disclosed.

Abstract: A suspension system suitable for a flux gate compass having compass windings (14) includes a ball joint (4,5,6) which permits both tilt and twist about a vertical axis, and a separate alignment element (16) for causing the windings to follow twisting motion of the fixed structure. The alignment element takes the form of a flexible printed circuit made into a double spiral form and carrying electrical conductors to provide the electrical connections to the windings. A zig-zag shape may be used instead of a spiral. The suspension does not suffer from the geometric imperfections of a Hooke's joint and avoids the need for separate flexible conductors which can interfere with the suspension operation and can break.

Abstract: An apparatus for inhibiting the oscillation of a vertical crane or similar structure with a horizontal main jib supporting a load hoist apparatus. The main jib has a counter jib which supports a counterweight mass by a linkage system. The linkage system permits the counterweight mass to swing through an arc so that it dampening the swinging movement of the crane. The linkage system also permits the counterweight mass to be vertically adjustable relative to the main jib so as to accommodate crane structure of different sizes.

Abstract: A magnetic compass has been devised which is of the type having a pivot point displaced above the plane of the permanent magnets so that the distance of displacement of the pivot point with respect to the center of force will reduce the tilt angle or tipping otherwise caused by changes in latitude when the compass is to be operated in different parts of the world and a spherical needle bearing can be employed at the pivot point as a result of the increased pendular effect achieved by displacing the pivot point above the magnets. The need for a lift assembly to cushion the pivot point is eliminated while providing for an extremely rugged and versatile magnetic compass which will serve as a light, portable pocket transit capable of measuring horizontal and vertical angles as well as being used as a prismatic compass, level, clinometer, plumb or alidade.

Abstract: An alignment device comprising a plurality of hollow arcuate sections secured together at their inner edges so as to form a hollow center with a base support member, an aperture for admitting fluid and scalar indicia about the outer edges of the arcuate section. The device may be adapted to removably accept a rigid rod opposite said base, said rod being adapted for insertion into the chuck of a drill.