Abstract:
In a variable compression ratio internal combustion engine in which the compression ratio is changed by changing the combustion chamber volume, the present invention enables to inhibit irregularities in the air-fuel ratio involved by changing of the combustion chamber volume. In a transition period during which the compression ratio is changed, the actual volume of the combustion chamber realized by a compression ratio changing mechanism is detected. A factor that influences the air-fuel ratio (for example, fuel injection quantity, cylinder intake air quantity or amount of EGR) is controlled based on the actual volume of the combustion chamber thus detected to make the air-fuel ratio substantially equal to that before and after the change of the compression ratio.
Abstract:
A device and method for determining a temperature variable, in particular a temperature variable that characterizes the condition of an exhaust-gas treatment system of a combustion engine, are described. The temperature is specified on the basis of variables that characterize the mass flow in the exhaust-gas treatment system, and/or of a second temperature variable that characterizes the temperature upstream from the exhaust-gas treatment system.
Abstract:
The flow meter is a device having a laser Doppler anemometer (LDA) which measures the instantaneous center line velocity of fluid flow in a pipe and processes the instantaneous velocity so obtained to compute the volumetric flow rate, mass rate, and other flow characteristics as instantaneous quantities and/or integrated over a time interval using an electronic processing method which provides an exact solution to the Navier-Stokes equations for any periodically oscillating flow. The flow meter is particularly adapted for measuring the flow characteristics of high pressure automotive fuel injection systems. Three embodiments of the flow meter are described, including a stationary stand for off-line bench testing flow rate in a fuel injection system, a portable flow meter for inline testing in a vehicle's fuel line, and an on-board flow meter sensor connected to an engine control module.
Abstract:
An engine control system that identifies fuel dynamical steady state (FDSS) includes a cylinder and a controller that determines a detection period. The controller monitors a mass of fuel ingested by the cylinder during the detection period. The controller identifies FDSS if the mass of fuel remains within a predetermined range during the detection period.
Abstract:
A method and apparatus for injecting pilot fuel in a combustion engine. The method and apparatus includes determining a load of the engine, determining a desired injection timing of the pilot fuel and a desired quantity of pilot fuel to be injected as a function of a desired homogeneous distribution of the pilot fuel based on the engine load, and adjusting the injection timing and quantity of the pilot fuel to the desired values.
Abstract:
A method and system for controlling fuel mass during transient engine conditions is based on an open loop transient fuel compensation algorithm so as to provide transient fuel compensations that address drivability requirements associated with the acceleration mode and deceleration mode of engine operation as well as the ease of the calibration during engine cranking mode.
Abstract:
The present invention provides a method and apparatus using a gas concentration sensor for accurately controlling an air fuel ratio in an internal combustion engine, featuring in that before the fuel-vaporized gas purged from the canister enters into the intake manifold whereat the sensor detects the gas concentration of the purged gas, the sensor is adjusted so as to adjust a zero point (or zero output level) of the sensor output. In step 100 of FIG. 7, a judgment is made as to whether the flow rate of air reaches a predetermined level. In step 110, processing for zero-point correction of the gas concentration sensor is performed. Specifically, in a state in which the purge valve 17 is closed, concentration of purge gas is measured by use of the gas concentration sensor 4, and a sensor output S1 at that time is obtained. Subsequently, the sensor output S1 is compared with a correct sensor output S0 in order to obtain a difference &Dgr;S therebetween. Accordingly, during subsequent gas concentration measurement, a value S3 obtained through subtraction of the difference &Dgr;S from an obtained sensor output S2 is used as a correct sensor output. In step 120, a supply amount of purge gas, i.e., a concentration of the purge gas to be supplied is obtained. In subsequent step 130, the purge valve 17 is driven in order to supply purge gas to the intake pipe 2 in a required amount (A%).
Abstract:
An engine control device comprising a reference voltage memory means 21 for memorizing reference voltage VAFS_STD of AFS9 for controlling an engine 1 under a normal state, a comparing means 22 for comparing an output voltage VAFS from the AFA9 when the engine 1 is stopped with the reference voltage VAFS_STD and operating a deviation nullVAFS, and a corrections means 23 for correcting the output voltage VAFS from the AFS9 based on the deviation nullVAFS so that the output voltage VAFS becomes the reference voltage VAFS_STD, wherein a fuel injection quantity Tinj is operated based on the output voltage VAFS_OBJ from the sensor obtained by the correction means 23, whereby engine stall caused by failure of the sensor for controlling the engine is avoidable.
Abstract:
A system for controlling a vehicle drivetrain in a fuel-efficient manner includes, in one embodiment, a control computer operable to determine a number of engine load/engine speed boundary conditions as functions of brake specific fuel consumption (BSFC) contours in relation to an engine output characteristics map and define therefrom an undesirable engine operation region U. As long as the engine is engaged with at least one of the gear ratios of the vehicle transmission, the control computer is operable to maintain or encourage engine operation outside of the region U. In another embodiment, the control computer is operable to define a contour from substantially zero engine load to substantially full engine load, wherein the contour preferably corresponds to a fuel-efficient path from no-load to full-load engine operating conditions. With change gear transmissions, the control computer is operable to control transmission shift points about the contour. With continuous variable transmissions, the control computer is operable to modify the effective gear ratio thereof to maintain engine operation on or about the contour. In either case, fuel efficient operation may be optimized.
Abstract:
A sensor array for detecting the distribution of fluids having different electrical characteristics, comprising a multilayer structure including a first layer which defines an array of spaced apart sensor electrodes, a second layer separated from the first layer by dielectric material and defining a conductive screen, and a third layer separated from the second layer by dielectric material and defining a series of spaced apart elongate connections, each sensor being connected to a respective connection by a respective conductive path extending through an opening in the conductive screen defined by the second layer.