Abstract: A device for measuring relative distance between two physical objects includes an elongated inductor coil and a movable core. The movable core includes a slug of magnetically interactive material and is configured to move within the elongated inductor coil and to couple and interact magnetically with the elongated inductor coil. Electric current flowing through the elongated inductor coil generates a magnetic flux within the elongated inductor coil, and the magnetic flux is subsequently modified by moving the movable core within the elongated inductor coil and the modified magnetic flux is used to produce an electric output as a function of the position of the slug within the elongated inductor coil.

Abstract: Sensor circuits including an oscillator circuit.

Abstract: Position sensor circuits are disclosed for use with variable reluctance sensors. Variable reluctance sensors are described for linear, angular and rotary position measurement and for acceleration measurement.

Abstract: Sensor circuits including an oscillator circuit.

Abstract: Electromagnetic actuators are described for operating poppet valves in internal combustion engines.

Abstract: A precision pump for moving small volumes of fluid includes an electromagnet in which is reciprocally mounted an armature carrying a diaphragm on one end such that upon reciprocal movement of the armature an alternating high and low pressure can be created in a pumping chamber to move fluid through the pump. In one embodiment of the pump, the electromagnet drives the armature in one direction and a spring returns the armature to effect the reciprocating movement while in a second embodiment a pair of electromagnets are axially aligned and cooperate with a pair of magnets on the armature to alternately move the armature in a linear reciprocating motion as current is alternately applied to the electromagnets.

Abstract: A breath alcohol detector measures and compensates for distance between the mouth of the individual exhaling breath into the ambient air and the detector, the atmospheric pressure, and the temperature. Blood alcohol content information is calculated using these compensation factors and a signal obtained from an electrochemical fuel cell which is indicative of the amount of alcohol or other gas contained in the sample. The detector also includes a reciprocally acting electromagnetically energized motor which drives a diaphragm pump to draw the sample into the electrochemical fuel cell.

Abstract: A portable oilfield fluid management system and method provides display information concerning fluid status and includes a plurality of local sensing units which can be selectively attached in any order to a plurality of different storage tanks having different sizes, shapes and capacities located in different oilfields. A plurality of cable segments each of equal predetermined length are used to interconnect the attached local sensing units to each other in a serial connection and a central touch activated monitor located away from the local sensing units is interconnected to the first attached local sensing unit by means of an elongated cable. Because the local storage units which function to measure the level of fluid in the storage tanks can be attached to the storage tanks in any order, the central touch-activated monitor autoconfigures the local sensing units by assigning binary addresses to each attached local sensing unit.

Abstract: A storage tank level monitoring apparatus and method for determining fluid levels in a storage tank. The apparatus of the present invention includes a magnet coated with rubber for holding a pivotally mounted housing to the interior of the storage tank and an ultrasonic transducer contained within the housing for generating acoustic pulses and for receiving reflections of the acoustic pulses for producing an analog signal proportional to the reflections, a string carrying a number of reference disks vertically oriented below the housing for producing a series of reflected acoustic signals from each reference disk, and a processor connected to the ultrasonic transducer for activating the transducer and for analyzing the reflected pulses for calibrating the apparatus for environmental changes in the atmosphere above the stored fluid and for determining the level of the stored fluid in the tank.