Ford Motor Company Limited

Ford Global Technolgoies, LLC

Alex D Colvin

James W Butler

Thomas J Korniski

Joseph C Cassatta

Keith R Carduner

Dick Y Leong

Richard E Soltis

Jeffrey A Cook

Jessy W Grizzle

James S Rankin

Dennis Schuetzle

Kenneth Miller Junkins

Daniel J Graham

Paul D Maker

A portable exhaust gas flow sensor includes a tube for coupling to an exhaust pipe of a vehicle and having a thin screen or similar flow restricting element to induce a pressure drop based on the exhaust gas flow with an upstream port and a downstream port relative to the flow restricting element connected to a differential pressure transducer. A thermocouple extends through a temperature port to measure exhaust gas temperature flowing through the tube. A processor in communication with the thermocouple and the differential pressure transducer determines the exhaust gas flow based on the differential pressure and the temperature. The flow restricting element includes sufficient spaces to resist formation of condensation and minimize added back pressure while providing an accurately measurable pressure drop for flows ranging from idle to full throttle.

Portable vehicle exhaust flow sensor

A portable exhaust gas flow sensor includes a tube for coupling to an exhaust pipe of a vehicle. The tube includes a circular flow restricting element to induce a pressure drop based on the exhaust gas flow with an upstream port and a downstream port relative to the flow restricting element connected to a differential pressure transducer. A thermocouple extends through a temperature port to measure exhaust gas temperature flowing through the tube. A processor in communication with the thermocouple and the differential pressure transducer determines the exhaust gas flow based on the differential pressure and the temperature. The circular flow restricting element includes sufficient spaces to resist formation of condensation and minimize added back pressure while providing an accurately measurable pressure drop for flows ranging from idle to full throttle.

Electronic circuitry and control algorithms are described to automatically establish the output voltage of a linear exhaust gas oxygen sensor (e.g., a UEGO sensor) corresponding to an exhaust air-fuel ratio of stoichiometry. The apparatus and control logic herein described may be used to adaptively correct the setpoint of an air-fuel ratio control system in which a UEGO sensor is used in a feedback loop to adjust the fuel injection quantity of an internal combustion engine.

Control approach for use with dual mode oxygen sensor

A conductivity sensor ( ) and control circuit ( ) for determining the conductivity of a fluid is provided. Conductivity sensor ( ) is formed of a first annular electrode ( ) spaced apart from a second annular electrode ( ) having a tubular portion ( ) therebetween. The first annular electrode ( ) and the second annular electrode ( ) are coupled to a control circuit ( ). The control circuit ( ) preferably includes a square wave generating circuit ( ), a current-to-voltage converter circuit ( ) coupled to one of the electrodes, a buffer circuit ( ) coupled to the other one of the electrodes, a synchronous detector circuit ( ). The synchronous detector circuit ( ) is operated using the square wave from square wave generator circuit ( ). By oscillating between a negative and positive gain, a constant direct current output corresponding to the conductivity of the fluid between the first annular electrode and second annular electrode is provided.

Conductivity sensor for detecting conductivity of a fluid

An apparatus ( ) for measuring the amount of air entrained in the fluid of a power steering pump. The apparatus includes a fluid conduit ( ) having a connector ( ) adapted to connect to a power steering pump ( ) with the fluid conduit ( ) in fluid communication with the internal fluid cavity ( ) of the power steering pump ( ). A pressure gauge ( ) is operatively connected to the fluid conduit ( ) for determining the pressure in the power steering pump ( ), and a meter ( ) is operatively connected to the fluid conduit ( ) for measuring the rate at which mass is removed from the power steering pump ( ). The apparatus further includes a vacuum pump ( ) operatively connected with the fluid conduit ( ) for drawing air out of the power steering pump ( ).

Apparatus for measuring the amount of air entrained in a fluid

A method and apparatus for controlling air/fuel ratio of an internal combustion engine at a desired level of richness or leanness utilizes an existing air flow sensor for sensing air flow into the engine and generating a corresponding air flow signal. A signal multiplier multiplies the air flow signal by a constant to generate a modified air flow signal corresponding to the desired level of richness or leanness. A control signal is then generated for controlling the air/fuel ratio to the desired level.

Method and system for predictably controlling air/fuel ratio

A method and system for determining steady state and real time engine oil consumption of an automotive engine which generates exhaust gases containing oil and fuel having a known sulphur content. The system includes an exhaust gas conditioner coupled to the exhaust manifold of the engine for extracting an exhaust gas sample and converting the exhaust sample into a combustion product. The system also includes a high temperature sampler for automatically regulating the amount of the combustion product independent of changes in back pressure of the engine. The system further includes a fluorescent detector for generating a sulphur dioxide content signal having a value corresponding to the sulphur dioxide contained in the regulated combustion product. Finally, the system includes a processor responsive to the value of the sulphur dioxide content signal to determine a steady state and/or a real time oil consumption of the engine based on the value of the sulphur dioxide content signal and the known sulphur content of the oil and fuel.

Method and system for determining engine oil consumption

Exhaust gas constituents of an exhaust gas stream are measured by drawing a proportional sample of exhaust gas through a capillary tube inserted into the exhaust gas stream. The capillary tube is controllably heated to avoid distortion of the reading due to condensation. The mass flowing in the capillary tube is determined by sensing the pressure drop across the length of the capillary tube.

Probe for exhaust gas sampling

A method and associated apparatus for on-line gas analysis of a multicomponent gas emission flow, comprising: continuously withdrawing and regulating the pressure of a first sample flow from the emission flow, continuously withdrawing a second sample flow from the first sample flow, the second flow sample being diluted with mass controlled amounts of diluent (N.sub.2 or air) to lower the dew point of the gas sample to below room temperature; controlling the absolute pressure of the diluted sample to the range of 920-950 mbar; frequently periodically analyzing the diluted sample flow, controlled as to pressure, by fourier-transform infrared spectrometric techniques to render a concentration measurement for each desired gas species; and correcting each concentration measurement for dilution to derive an undiluted concentration measurement representative of the actual exhaust gas, said correction being accomplished by measuring the actual air/fuel ratio of the gas emission flow to provide a theoretical carbon concentration in the undiluted exhaust gas and thereafter ratioing the theoretical total carbon concentration to the measured carbon concentration in the sample to provide the needed correction factor.

Direct sampling of engine emissions for instantaneous analysis

A system for measuring an automotive engine exhaust constituent includes a meter for measuring the mass of air flowing through the engine and for generating a flow signal corresponding to the airflow, and a sample handling apparatus for separating a fraction of the exhaust flowing through the engine and for conducting the exhaust fraction to an analyzer. The system further includes diluent adding means for doping the extracted exhaust fraction with a diluent gas upstream of the analyzer and a processor for receiving the mass flow signal from the engine mass flow meter and for operating the diluent adding device in response to the flow signal. The processor operates the diluent valve such that the flow rate of exhaust gas into the analyzer remains a relatively constant fraction of the total exhaust flowing from the engine.

System for measuring engine exhaust constituents

Provided is a method and circuit for measuring on a real-time basis trace constituents in vehicle engine exhaust. The control circuit operates to maintain a small, constant concentration of a selected electrolyte constituent reactive with the exhaust constituent sought to be measured. The amount of current necessary to regenerate and maintain the concentration of the selected electrolyte constituent is continuously measured to generate a real-time electrical signal proportional to the mass flow of the exhaust constituent entering the electrochemical cell.

Method and control circuit for measuring trace constituents in

A method and apparatus for linearly determining the air/fuel ratio of an internal combustion engine by measuring the oxygen concentration of the exhaust gases provides a linear air/fuel output signal from a single sensor. The sensor is time shared between a current driving or oxygen pumping mode in which a current is applied to the sensor to pump oxygen through the sensor toward one or the other surface, and a voltage sensing mode in which the voltage across the sensor is monitored. A time share circuit switches between the two modes of operation. During the current mode, the oxygen concentration is changed at the sensor surface by the passage of oxygen ion current through the sensor. During the voltage mode, the sensor voltage is measured. Feedback provides necessary current during the current mode to hold the bias voltage substantially constant. The resulting current is a linear measure of the air/fuel ratio of the internal combustion engine as engine operation departs from stoichiometry. The sensor current can be positive or negative and hence will indicate both rich and lean mixtures.

Linear air/fuel sensor

A method and apparatus for measuring the electrical conductivity of a liquid comprises an electrically insulating housing through which the liquid flows, and four electrodes inserted into the path of the liquid flowing through the housing. The first and third electrodes are current electrodes and the second and fourth electrodes are voltage electrodes. An AC current is injected into the first current electrode and exits at the second current electrode, with the resulting AC voltage across the voltage electrodes being measured. The first current electrode is driven to maintain a constant value of AC voltage on the voltage electrodes while measuring the current flow in the second current electrode which is representative of the electrical conductivity of the liquid. A DC bias voltage source is provided and is coupled to each of the electrodes by a resistor and a capacitor to prevent coating or plating of the electrodes. The method and apparatus permit continuous monitoring of the absolute conductivity of a liquid.

Continuous measurement of the absolute conductivity of a liquid

A circuit and method for measuring the capacitance of a medium independent of the resistivity of the medium. A triangular voltage is applied to plates immersed in the medium to generate both a resistive current component in phase with the triangular voltage and a capacitive current component in phase with a differential of the triangular voltage. The resistive and capacitive current components are summed with a selectable current which is provided having a phase .pi. radians out of phase with the triangular voltage and having an amplitude related to a control signal. The summed current is sampled over a time period phase shifted from the capacitive current component and then integrated so that the capacitive current component integrates to zero and the integral of the resistive current component minus the selectable current provides the control signal. In response to the control signal, the selectable current is varied until the sum of the selectable current and resistive current component are nulled. This summed current is then sampled in phase with the capacitive current component thereby obtaining a measurment of capacitance independent of resistance.

Capacitance measuring apparatus with means for nulling the resistive

A method is disclosed of making an on-line gas analysis of a multicomponent gas emission flow by (a) continuously sequestering a sample flow from the gas emission flow, which sample flow may be filtered to substantially eliminate solid or liquid particles, diluted to lower its dew point to below room temperature, and changed in either temperature and/or pressure to be substantially the same in temperature and pressure as that of gases used to create reference transmission frequency spectral data employed in step (d); (b) continuously irradiating the sample flow with an electromagnetic radiation beam while modulating the amplitude of infrared frequencies in the audio frequency range of the beam, either prior to or immediately subsequent to irradiation of the sample flow, to produce electromagnetic signals having discernible amplitude variations resulting from spectral interference patterns; (c) detecting and collecting the signals at a sufficiently high rate to substantially completely distinguish between adjacent spectral pattern amplitude peaks without mutual spectral interference and to permit analysis of the signals in real time; and (d) analyzing the signals in real time by (i) mathematically manipulating the signals in accordance with Beer's Law to create reformed background-corrected data, and (ii) applying reference transmission frequency spectral data to the reformed data for each suspected gaseous component to give a linear quantitative measure of the presence of each and every suspected gas component in the gas emission flow.

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Oak Park, MI, United States of America

Alex D Colvin