Abstract: MOSFETs are provided to connect the sensor input terminals of a ratiometric output sensor to a pair of power terminals, and the gate of each MOSFET is coupled to the opposite power terminal so that both MOSFETs are rendered conducting to power the sensor when a supply voltage of a predetermined polarity is connected across the power terminals but one of the MOSFETs is rendered non-conducting when a voltage of the opposite polarity is so applied. The MOSFET that is rendered non-conducting is oriented so that any internal source-drain diode does not bypass current around the MOSFET when voltage of the opposite polarity is applied. Optionally, over-voltage protection is provided by an input voltage sensor controlling the other MOSFET through a third MOSFET.

Abstract: A sensor circuit is coupled to a sensing element for determining a property, such as a dielectric constant, of a fuel suitable where the dielectric constant is used in determining a concentration of ethanol in the gasoline/ethanol blended fuel. The circuit includes an excitation voltage signal generator, a synchronization trigger and a processing circuit configured to generate an output signal indicative of the fuel property (dielectric constant). The excitation voltage signal is applied to the sensing element to produce an induced current signal therethrough. The synchronization trigger is configured to generate a trigger signal when the excitation voltage signal crosses zero volts, at which time the real (resistive) component of the induced current signal is zero.

Abstract: A capacitive pressure sensor includes a electrically conductive, generally piston shaped diaphragm with a flexible base wall configured to deflect under pressure. The diaphragm is generally U-shaped in cross section. The base wall includes an upper, flat sensing surface which acts as a capacitive electrode. The diaphragm further includes a step around a radially-outermost perimeter which is elevated from the flat sensing surface. A sensing electrode body is located on top of the step and creates a capacitive sensing cavity between the sensing surface and the bottom surface of the electrode body. On the bottom surface of the electrode body is formed a center, circular electrode and a ring electrode that surrounds the center electrode. The center electrode and the sensing surface form a variable capacitor which changes with pressure and the ring electrode and the sensing surface form a reference capacitor.

Abstract: A valve has a plunger that is moved by an actuating solenoid. The actuating solenoid surrounds a large diameter segment of the plunger. A smaller position sensing coil surrounds a smaller diameter segment of the plunger (and is thus coaxial with the larger actuating solenoid) for outputting a signal representative of the position of the plunger.

Abstract: A sensing assembly senses a level of a fluid in a reservoir. The sensing assembly includes a first input port for receiving a first input voltage signal. The sensing assembly also includes a second input port for receiving a second input voltage signal. An excitation circuit is electrically connected to the first and second input ports for receiving the first and second input voltage signals and for generating a first excitation signal and a second excitation signal. A receiving circuit is disposed adjacent the excitation circuit and defines a variable capacitance with the excitation circuit. The receiving circuit produces an output voltage variable with the level of the fluid in the reservoir due to capacitance changes between the excitation circuit and receiving circuit. The receiving circuit includes first receiving electrode configured to effect linear capacitance change with fluid level and a second receiving electrode configured to effect second order linear capacitance change with fluid level.

Abstract: In a planar oxygen sensor having a pump cell, a reference cell, a sensor chamber and a heating device, a ground plane electrode is provided and includes a sensing portion having a first sense lead and a second sense lead and a measuring portion having a first measuring lead and a second measuring lead, wherein the first measuring lead and the second measuring lead have increased surface area relative to said sensing portion such that the resistance between the first measuring lead and the second measuring lead is reduced and wherein the first measuring lead is disposed so as to be communicated with the first sense lead and the second measuring lead is disposed so as to be communicated with the second sense lead.

Abstract: A method for detecting fuel leaking into an oil pan containing oil which is used to lubricate an internal combustion engine utilizes a plurality of sensors. The method includes the step of measuring a plurality of parameters of the oil using each of the plurality of sensors to create measured values. A fuel leakage value is calculated incorporating each of the measured values. The method then determines when the fuel leakage value exceeds a predetermined value.

Abstract: A control circuit for a vehicle for, e.g., chassis leveling or other purposes includes a controller selectively sending drive signals to a load through a switch FET, and a BJT having a collector connected between the switch FET, an emitter connected to ground, and a base connected to a current view resistor for short circuit protection. An over power protection FET is connected to the controller and to the base of the short circuit protection transistor, with the gate of the over power protection FET being connected to the output of the switch FET. A time delay capacitor is connected from the base of the BJT to ground. With this structure, if a ground fault causes the BJT to turn on, and if the drain-source voltage of the switch FET exceeds the gate threshold voltage of the overpower protection FET, the overpower protection FET is turned on, resulting in turning off the switch FET and, hence, avoidance of high power draw through the switch FET.

Abstract: A method for detecting fuel leaking into an oil pan containing oil which is used to lubricate an internal combustion engine utilizes a plurality of sensors. The method includes the step of measuring a plurality of parameters of the oil using each of the plurality of sensors to create measured values. A fuel leakage value is calculated incorporating each of the measured values. The method then determines when the fuel leakage value exceeds a predetermined value.

Abstract: A method for determining fuel dilution of diesel engine lubricating oil in a diesel engine. A first table contains a soot compensation factor, respectively, for each weight of oil selected among a predetermined range of oil weights. A second table contains fuel dilution levels for a plurality of predetermined compensated viscosity ratios. After determining the weight of the oil in the engine a first viscosity of the oil at a first temperature and a second viscosity of the oil at a second temperature are measured. Next, either a ratio or a difference of the first and second viscosities is determined. Using the ratio, soot in the oil is compensated using a soot compensation factor of the first table which is respective of the oil to thereby provide a compensated viscosity ratio. Finally, the compensated viscosity ratio is compared with the second table to thereby determine the fuel dilution level.

Abstract: MOSFETs are provided to connect the sensor input terminals of a ratiometric output sensor to a pair of power terminals, and the gate of each MOSFET is coupled to the opposite power terminal so that both MOSFETs are rendered conducting to power the sensor when a supply voltage of a predetermined polarity is connected across the power terminals but one of the MOSFETs is rendered non-conducting when a voltage of the opposite polarity is so applied. The MOSFET that is rendered non-conducting is oriented so that any internal source-drain diode does not bypass current around the MOSFET when voltage of the opposite polarity is applied. Optionally, over-voltage protection is provided by an input voltage sensor controlling the other MOSFET through a third MOSFET.

Abstract: A pressure control valve assembly includes a linear actuator portion and a hydraulic portion. The linear actuator includes an improved plunger that has an enlarged diameter portion near the secondary plate. The linear actuator further includes a plunger-to-primary plate interface that has a double step magnetic configuration, which increases the force developed on the plunger.

Abstract: A semi-circular dielectric rotor is attached to a steering column for rotation with the steering column. Straddling the rotor but not contacting it are an excitation electrode member which generates an electric field and a receiver electrode member that outputs signals representative of the electric field and, hence, of the position of the steering column.

Abstract: Certain characteristics of Diesel engine lubrication oil are determined. A sensor formed as a capacitor is immersed in the oil. An inductor is in series with the sensor, and a high frequency voltage with a varying frequency is applied to the resonance circuit formed by the inductor and capacitor. Resonance is sensed, and the resonant frequency and/or the resonant current are used to determine the soot content and/or the dielectric constant of the oil. The electronics temperature can be used to compensate for temperature variations in the resonant frequency and the electronics temperature and the oil temperature can be used to compensate for temperature variations in the resonant current. The compensated values are preferably used in the determination of soot content and the dielectric constant.

Abstract: A method for detecting fuel leaking into an oil pan containing oil which is used to lubricate an internal combustion engine utilizes a plurality of sensors. The method includes the step of measuring a plurality of parameters of the oil using each of the plurality of sensors to create measured values. A fuel leakage value is calculated incorporating each of the measured values. The method then determines when the fuel leakage value exceeds a predetermined value.

Abstract: A sensor comprises: a pump cell comprising an inner pump electrode, an outer pump electrode, a pump cell electrolyte layer interposed between the inner pump electrode and the outer pump electrode and a cell isolation layer disposed on the inner pump electrode on a side opposite the pump cell electrolyte, wherein the outer electrode is in fluid communication with a reducing gas. A reference cell is in operable communication with the pump cell, the reference cell comprising an outer reference electrode and an inner reference electrode, and a reference cell electrolyte interposed between the outer reference electrode and the inner reference electrode.

Abstract: A viscosity measurement apparatus, or viscometer, including a fluid flow channel, a heating element disposed at least around an exterior portion of the fluid flow channel near an inlet end, and a temperature sensor disposed within the fluid flow channel downstream from the heating element. The viscometer may also include a thermally insulating jacket disposed around the heating element and the fluid flow channel. A method of measuring viscosity with the viscometer includes immersing a fluid flow channel in the fluid, heating a portion of the fluid in the fluid flow channel near the inlet end of the fluid flow channel, and measuring a temperature of the fluid in the fluid flow channel at a position downstream from the inlet end of the fluid flow channel. The method further includes recording temperature changes of the fluid for a time period and comparing recorded temperature change characteristics to known fluid viscosities to determine viscosity.

Abstract: Circuit system and method for receiving and demodulating signals to a tire pressure monitoring system. The circuit comprises a demodulator for receiving an input signal modulated at a first frequency and demodulating the input signal so that information can be extracted from the input signal at a second frequency lower than the first frequency. The circuit further comprises a microprocessor, operating at a clock rate selected to extract information from the demodulated signal at the second frequency, for receiving and decoding a demodulated signal from the demodulator. In another aspect, the demodulator comprises a switching circuit having a time constant longer than the period of the first frequency.

Abstract: A sensor assembly for measuring linear position is provided. The assembly comprises a ferromagnetic magnetic flux concentrator. The flux concentrator is configured as a generally rectangular structure including an air gap at one side thereof. A magnet is slidable along the longitudinal axis of the concentrator. A galvanomagnetic sensing element is disposed in the air gap for sensing magnetic flux passing therethrough. The sensing element is configured to provide an output signal indicative of the measured linear position as the magnet travels along the longitudinal axis of the concentrator.

Abstract: In a linear position encoder, a support is provided upon which a pair of phase quadrature windings are mounted. The windings are arranged to have a sinusoidal magnetic sensitivity characteristic along the length of the support. Mounted on a movable element there is a resonant circuit including a coil and capacitor that can magnetically couple with the windings. When the circuit is excited, it induces currents in the windings that are dependent upon the position of the circuit within a period Ts of the windings. An excitation and processing unit is provided to energize the circuit and to process the signals induced in the windings. The excitation and processing unit is operably coupled to an external high permeability rod extending along the measurement path in a first plane having the windings but removed therefrom. The rod has first and second excitation coils connected in series and wound around the rod and disposed at opposite ends defining a length of the rod.