Motorola Corporation

Engelhard Corporation

Neil J Adams

Daniel A Young

Donald J Remboski

Jeffrey D Naber

Jose P Joseph

Steven L Plee

Seajin Oh

Chowdary Ramesh Koripella

Craig R Markyvech

Adam Moya

Gerald Stephen Koermer

Linda Hratko

Kevin J Bush

Patrick W Blosser

David Frankowski

Gary K Mui

Armand R Losinski

Edward Balko

Jie Xue

Sanjay Dua

Adam Miller

Jeff Naber

Dao Duong

A spectral method, and corresponding system, for knock detection includes acquiring ( ) spectral energy associated with vibration caused by a knocking condition from a running engine. Preferably, a sampled data system ( ) acquires the spectral energy by converting an output from an accelerometer ( ) into data samples ( ) in a digital form. Then from the acquired spectral energy, a knock variable is derived from magnitudes of spectral components, representing a characteristic of a combustion chamber located within the running engine. In a preferred embodiment the knock variable is derived from magnitudes of spectral components related by ratios corresponding to Bessel function coefficients. The preferred embodiment includes a Digital Signal Processor ( ) applying a Fast Fourier Transform method ( ) to estimate a spectral content used to determine the knock variable. Then, a knock indication is provided ( ) when the knock variable exceeds a magnitude of a predetermined threshold ( ). Other embodiments include provision for providing a knock indication when a knock variable ( ) derived from magnitudes of individual spectral components corresponding to characteristic knock spectra associated with acquired spectral energy exceeds a magnitude of a trended time weighted version of the knock variable by a predetermined magnitude ( ).

Spectral knock detection method and system therefor

A differential calorimetric gas sensor (10) which includes a sensing element (12) having a catalytic layer (14) disposed on a multi-layered substrate (26). Catalytic layer (14) includes an active catalyst region (14a) which oxidizes total combustibles within an exhaust gas stream and a reference catalyst region (14b) which oxidizes selective combustibles within the exhaust gas stream. An electrochemical oxygen source (18) is disposed on an opposite side of multi-layer substrate (26) from sensing element (12). An oxygen sensor cell (170) may be incorporated into electrochemical oxygen source (18). The multi-layered substrate (26) includes a plurality of overlaying insulating layers in which an intermediate layer (60) and a bottom layer (64) support primary heaters (58, 62), and in which another intermediate layer (52) supports compensation heaters (50a, 50b). The primary heaters (58, 62) function to maintain sensor (10) at a substantially constant temperature, while the compensation heaters (50a, 50b) function to restore temperature deviations determined by temperature-sensitive elements (46a, 46b) located on an inner layer (48) overlaying the compensation heaters (50a, 50b) resulting from the catalytic reactions taking place at the surfaces (34a, 34b) of the catalyst regions (14a, 14b). The control circuitry (300) operates to control the primary heater (58, 62) and the compensation heaters (50a, 50b), as well as to minimize the response variations of the temperature-sensitive elements (46a, 46b).

Exhaust gas sensor

A sensor housing (10) for directing the flow of a gas over two sensitive regions (53, 54) of sensing device (52) includes an inner shroud (12) surrounding the sensing device (52). The inner shroud (12) is inserted into an outer shroud (14), such that a plurality of gas channels (44) are formed between the inner shroud (12) and the outer shroud (14). In operation, a gas enters through inlet orifices (28) in the outer shroud (14) and travels through the gas channels (44) to the proximal end (26) of the inner shroud (12). The flow direction of the gas is then reversed and the gas passes through an inner chamber (50) and over sensitive regions (53), (54) located on the surface of the sensing device (52). Vacuum pressure created at an outlet hole (46) located at a distal end (35) of the outer shroud (14) draws the gas out of the inner chamber (50) and return the gas to the exterior of the sensor housing (10).

Sensor housing for a calorimetric gas sensor

A calorimetric hydrocarbon gas sensor (10) includes an electrochemical oxygen pump (18), a sensing element (12), and a multi-layered substrate (26) separating the sensing element (12) from the electrochemical oxygen pump (18). The multi-layered substrate (26) includes a plurality of overlying insulating layers, in which at least one intermediate layer (60) supports a first primary heater (58), and in which another intermediate layer (52) supports a temperature compensation heaters (50a, 50b). The primary heater (58) functions to maintain the calorimetric hydrocarbon gas sensor (10) at a constant, elevated temperature, while the active compensation heater (50a) functions to maintain substantially equal temperatures as determined by the thermometers (46a, 46b) located on an intermediate layer (48) overlying the compensation heaters (50a, 50b). Control circuitry is integrated with power measurement circuitry to measure differences in the heat produced by the compensation heater (50a) and the thermometer (46a) in an active region (100), and the heat produced by the compensation heater (50b) and the thermometer (46b) in a reference region (102).

Calorimetric hydrocarbon gas sensor

A system and method measures hydrocarbon conversion efficiency of a catalytic converter (501). Total-combustible sensors (511, 521) are positioned to measure exhaust gas on both sides of the catalytic converter (501). Signals from these sensors (511, 521) have a magnitude comprised of a first portion, dependent on a concentration of the hydrocarbon gas in the gas stream, and a second portion, dependent on a concentration of the other combustible gasses in the gas stream, where a magnitude relationship between the first portion and the second portion is variable when the gas stream transitions into a region on the rich side of stoichiometry. The signals from these sensors (511, 521) are filtered so that a magnitude relationship between a first and second portion of the filtered signals is constant when the gas stream (506) transitions into the region on the rich-side of stoichiometry. Hydrocarbon conversion efficiency (529) is computed dependent on the filtered signals (515, 525).

System and method for measuring hydrocarbon conversion efficiency of a

A system and method estimates tailpipe emissions by sensing (703) a catalyzed gas stream (506) and providing a total-combustible gas signal (511) dependent thereon. The total-combustible gas signal (511) has a magnitude comprised of a first portion, dependent on a concentration of the hydrocarbon gas in the catalyzed gas stream (506), and a second portion, dependent on a concentration of the other combustible gasses in the catalyzed gas stream (506). A magnitude relationship between the first portion and the second portion is variable when the catalyzed gas stream (506) transitions into a region on the rich side of stoichiometry. The variability the magnitude relationship of the first and second portions is filtered out so that the magnitude relationship is substantially constant when the catalyzed gas stream (506) transitions into the region on the rich side of stoichiometry. The filtered signal is then integrated and compared to a threshold and an out-of-compliance signal (523) is provided when the filtered integrated signal (519) exceeds the threshold.

System and method for estimating tailpipe a emissions in a vehicle

A modified noble metal catalyst based calorimetric sensor for sensing non-methane hydrocarbons in an automotive exhaust gas stream includes a first sensing element (105) with an output that provides a signal (111) indicative of a concentration of indicative of non-methane hydrocarbons, hydrogen (H.sub.2), and carbon monoxide (CO). A compensating sensing element (107) has an output that provides a compensating signal (113) indicative of a concentration of hydrogen (H.sub.2) and carbon monoxide (CO). A circuit for combining the signal and the compensating signal provides a combined signal indicative of a measure of non-methane hydrocarbons in the automotive exhaust gas stream.

Modified noble metal catalyst based calorimetric sensor and method

A selective gas sensor (10) for detecting a particular compound, or group of compounds, such as non-methane hydrocarbons, within a high temperature gas stream (12) includes an oxygen generation system (14) positioned over an oxygen diffusion region (15). The oxygen generation system (14) and the oxygen diffusion region (15) provide oxygen through a medial temperature control zone (20) to a sensing element (16). The temperature and flux of hydrocarbon components within the high temperature gas stream (12) are regulated by components within the high temperature control zone (20) and by an external temperature control zone (22) in thermal contact with the sensing element (16).

Selective gas sensor

A system, and a corresponding method, for measuring a chemical concentration of a gas exhausted from exhaust ports (409, 413) of a multi-cylinder internal combustion engine (401) includes a gas sensing device. This device (419) is preferably a UEGO (Universal Exhaust Gas Oxygen) sensor. The gas exhausted is present in a substantially stable chemical concentration (706, 718) at a collection point (420) during intervals (738, 742) of engine angular rotation corresponding to the exhaust cycles. The UEGO sensor (419) measures the gas exhausted from the exhaust ports (409, 413) and provides a sensory output signal (743) that, during the intervals (738, 742) of engine angular rotation corresponding to each of the exhaust cycles, approaches (737, 741) a substantially stable value representative of the chemical concentration of the gas (706, 718) exhausted during the associated exhaust cycle. The sensory output signal (743) is coupled to an engine control system (431) that is executing signal reconstruction method steps (500, 600). These signal reconstruction steps (500, 600) are preferably based on a Kalman-Bucy state estimator in which a constituent gas signal P.sub.oe (745) that has a substantially constant amplitude during the intervals (738, 742), is reconstructed by the Kalman-Bucy state estimation reconstruction process (500, 600). The described improved method, and system, can compensate for the static and dynamic temporal and spacial effects, characteristic of the multi-cylinder engine exhaust system and the difference in sensory response to rich and lean exhaust gases, of the UEGO (419) sensor.

State estimator based exhaust gas chemistry measurement system and method

An apparatus, and corresponding method, for directly measuring air-fuel ratio of a combustion process, in an internal combustion engine is described. The apparatus includes a first electromagnetic wave sensor (105) that provides a first signal (107), representative of light intensity emitted at a first wavelength, and a second electromagnetic wave sensor (115) that provides a second signal (117), representative of light intensity emitted at a second wavelength. A ratio circuit (111, 121, 125) combines an integral of the first signal (107), and an integral of the second signal (117), and provides an air-fuel ratio signal, (127) indicative of the air-fuel ratio during the combustion process.

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Novi, MI, United States of America

Neil J Adams