Abstract: A proximity sensor has a resonant circuit which when stimulated by a pulse produces a signal with decaying oscillations. The number of such oscillations above a signal threshold varies in relation to the distance between a metal object and the proximity sensor. The sensor operation is configured by deriving a function that defines how the performance of a given proximity sensor deviates from performance reference data. The function is employed to normalize the count of oscillations produced by the given proximity sensor and the normalized count is used to determine presence of an object. By normalizing sensor performance, common configuration data can be used to setup a given proximity sensor without having to take into account specific performance variations of that sensor.

Abstract: In a two-wire electromagnetic flowmeter, an exciting coil generates a magnetic field in a direction perpendicular to the flowing direction of a fluid that flows through a measurement tube. A flow measuring output circuit adjusts an output current that flows to a pair of power supply lines to which an external power is supplied, in accordance with a flow measurement value obtained on the basis of a signal electromotive force which is generated in a direction perpendicular to the flowing direction of the fluid that flows through the measurement tube and the direction of the magnetic field generated from the exciting coil. An exciting circuit is connected in series with the flow measuring output circuit between the pair of power supply lines and supplies part of the output current to the exciting coil as an exciting current. In the exciting circuit, an exciting voltage circuit generates an exciting voltage between first and second lines.

Abstract: Some embodiments provide a sensor element, a shield element capacitively coupled to the sensor element and to ground, a coupling circuit to receive an input signal, and to electrically couple the received input signal to the sensor element and to the shield element, an output circuit to generate an output signal, the output signal based on a capacitance between the sensor element and an object, and a classifier to determine a material based on the output signal, and to transmit a material signal to the output circuit based on the determined material, wherein the output circuit is adjustable based on the material signal.

Abstract: A control system for a gas sensor element capable of lessening the effect of variations in sensor properties among gas sensor elements as well as the effect of environmental factors, such as temperature and humidity, to thereby accurately detect variation in the concentration of a specific gas. In a control system 10 for a gas sensor element 11 whose sensor resistance Rs varies with the concentration of NOx gas, a pulse signal Sc which alternates between 0 V and +5 V is input to a pulse input terminal 17. When a voltage of 5 V is applied to the pulse input terminal 17, a capacitor 14 is charged via a fixed resistor 15 having a resistance Rc and a diode 16. When a voltage of 0 V is applied, the capacitor 14 discharges via the gas sensor element 11. An output voltage Vout is A/D-converted and processed by means of a microcomputer 20, thereby controlling an electronic control assembly 21.

Abstract: An improved boiler water-level controller. According to one aspect of the present invention, a positive blowdown signal is presented to indicate to the operator that the alarm probe is in steam; performing blowdown until this indicator turns on helps ensure that the alarm probe is working properly. According to another aspect of the present invention, the controller uses a novel methodology of sensing water level using conductivity probes. An embodiment of this methodology uses the charging and discharging of a capacitor through a resistive value to sense the presence of water.

Abstract: A combined oil quality and fuel contamination sensing system includes a capacitive dielectric sensor and pressure sensing arrangements for measuring the dielectric constant of the oil and the pressure of the oil, respectively, with the oil pressure being indicative of oil viscosity and contamination. The sensors take measurements as oil flows through an internal combustion engine and provide an indication of the cause of a problem with oil in an engine. The system may also include a microcomputer and circuitry for generating an indication of dielectric constant and circuitry for generating an indication of the presence of contaminants within the engine. The system may also include an additional sensor measuring the temperature of oil within the system to adjust oil dielectric constant and viscosity indications. The capacitive dielectric sensor constitute the principal restriction in the flow path between an input high pressure sensing port and an outlet low pressure port.

Abstract: A wireless liquid sensing system includes a beverage container and a table top for holding the container. Embedded in the walls and bottom of the container are two electrically conductive plates coupled to a transponder wire coil. A reader radiates an RF signal at a predetermined frequency through a reader antenna. A microprocessor, also coupled to the transponder coil and the two plates, is powered by a rectifier circuit that gains power from then radiated RF signal. The microprocessor amplitude modulates the RF signal in accordance with the amount of liquid in the container. The reader can then detect this modulation with a peak detector to sense the amount of the substance in the container when the transponder antenna is inductively coupled to the reader antenna at the predetermined frequency.

Abstract: Detecting presence or absence of product in a reservoir by transmitting a signal affected by the product. The signal is detected from among other signals with which it is subsequently received by discrimination and delivery of an output signal whose level is set by the discrimination, and by sampling. Pairs of samples are correlated to obtain a true correlation value SR, where the instantaneous value of correlation between the state value B(i) and the state value B(i+Z) is summed, Z being the number of samples taken during a period T of the signal to be detected. A rate calculation is performed, during which the rate &rgr; of samples representing the presence of the signal is measured, and theoretical correlation mean values are evaluated. A decision is made by comparison of the true correlation value SR with each theoretical correlation mean value.

Abstract: The present invention concerns the capacitive vacuum sensor that includes an elastic diaphragm electrode and rigid fixed electrodes disposed to face opposite the elastic diaphragm electrode, with an internal space being delimited between the elastic diaphragm electrode and rigid fixed electrodes, wherein the elastic diaphragm electrode deflects elastically in response to any change in the pressure of a gas applied on the said elastic diaphragm electrode, and wherein the capacitive vacuum sensor is responsive to any change in the capacitance between the elastic diaphragm electrode and rigid fixed electrodes that may occur in accordance with the deflection of the elastic diaphragm electrode so that it can measure the pressure of the gas.

Abstract: An apparatus and method for determining power consumption in logic devices including mixed static and dynamic logic blocks is implemented. Input logical signals are tagged as having dynamical behavior or static behavior, and the power consumption of the logic block determined according to the behavior of the input signal. If an input signal has dynamic behavior, an output signal making a transition in response thereto will make two transitions per clock cycle, and the per cycle power consumption of the logic block is accordingly weighted. In another embodiment, a Boolean behavior signal is calculated for each block from clock phase tags and “one cycle per cycle” circuit level simulations. The per cycle power consumption of each logic block receives a weight in response to the Boolean behavior signal, according the behavior of the block characterized thereby.

Abstract: In order to monitor the consumption of a normally electrically conductive product contained in a storage chamber of a reservoir made of electrically non-conductive material, the storage chamber is disposed in a capacitive arrangement and a measurement procedure is defined, according to which, in response to an excitation signal applied to the capacitive arrangement, a measurement signal is obtained (at 122), one characteristic of which has an amplitude which varies substantially with the quantity of product contained in the storage chamber. Before deducing the value of information representing the quantity of product available in the reservoir from this amplitude, the measurement signal has filtering applied to it, according to which it is multiplied by a reference signal of frequency at least approximately equal to that of the excitation signal (at 121) and the multiplied signal is applied to a low-pass filter.

Abstract: A fault protective device (48) for limiting the maximum current and voltage applicable to electronic components and wiring (26, 30) located in the fuel tank (10) of an aircraft. Particularly, a fuel gauging system circuit (18) extends from a generator (20) located outside the tank to at least one probe (14) located in the tank and from the probe to instrumentation (24) outside the tank. The device is electrically coupled to the circuit at the tank wall (28) and includes a voltage clamp (50) and series inductor-capacitor resonant circuit (46), so that the resonant circuit provides a low series impedance when applied with a signal at the operating frequency of the input signal applied by the generator but provides a high series impedance when experiencing a signal of a different frequency indicative of a system fault.

Abstract: An apparatus and method for obtaining pressure data using a body implantable pressure sensor includes a measurement capacitor which is responsive to pressure changes of a body fluid. Non-constant, multiple current source charging of the measurement capacitor provides for a significant increase in sensitivity to conditions of pressure of a body fluid. Pressure data is obtained by charging the measurement capacitor at a first charge rate during a first charge period of an integration cycle and, during a second charge period of the integration cycle, charging the measurement capacitor at a second charge rate. The first charge rate is preferably greater than the second charge rate. The duration of the first and second charge periods may be varied. A signal indicative of a pressure change of a body fluid imparted to the measurement capacitor is produced by the pressure sensor. The signal may be a signal indicative of a change in a time of integration.

Abstract: A method and apparatus for dispensing fluids in response to a user request for a specified amount of the fluid. A microprocessor opens and closes a fluid port for predetermined amounts of time to control the amount of fluid dispensed. The microprocessor monitors the elapsed time and the amount of fluid that has been dispensed since the last time the filter was serviced. In one preferred embodiment, the amount of fluid that is dispensed is measured by continuously monitoring the volume of fluid flowing through the apparatus. A pressure measurement device allows the microprocessor to monitor the fluid pressure. The microprocessor prevents fluid from being dispensed if the pressure is not within a predetermined range of tolerances. The fluid port is opened and closed by activating and deactivating a solenoid. A keypad allows the user to input the amount of fluid that is to be dispensed.