Abstract: A method is provided for maintaining the speed of a spark-ignited internal combustion engine operating at a desired idle speed to compensate for engine speed variations caused by torque disturbances, utilizing an actual idle speed and the desired idle speed expressed as an RPM error ratio. A desired operating torque ratio is determined based on the torque available, a torque ratio reserve created by retarding spark from the maximum spark advance value and a torque ratio correction which reflects the torque disturbance. A desired final spark advance value is obtained from the desired operating torque ratio utilizing a nonlinear relationship between spark advance and torque ratio. The spark advance is modified to the desired final spark advance value so as to vary the torque supplied by the engine in order to maintain the desired idle speed.

Abstract: An air-fuel control that has two stages of operation. The control includes an EGO sensor interconnected to the exhaust system of an engine and a control assembly. In a first stage of operation, the engine is allowed to operate in an open loop condition. Periodically, however, the control momentarily moves to a second stage of operation. When in the second state, the control assembly ramps up the air-fuel ratio of the air-fuel mixture supplied to the engine until the EGO sensor changes state. The amount that the air-fuel ratio changed during this process is then compared with a nominal value to compute a correction factor. The correction factor is then used during the next open loop interval to increase or decrease the signal applied to the air-fuel distribution control and achieve a more optimum air-fuel mixture.

Abstract: A detection system and method for determining the phase relationship between a crankshaft and one or more independently phase shiftable camshafts which the system integrates into camshaft and cylinder identification sensors for determining both cam location for variable cam phasing, and for generating a cylinder identification signal uniquely identifying one of the cylinders, for sequential fuel injection, thus reducing: (i) the number of sensors needed to operate the system to a single crankshaft sensor and a single sensor for each camshaft; and (ii) the number of high-speed inputs needed on the on-board engine control unit microprocessor. The number of sensing teeth on the independent cam wheels vary depending upon the number of cylinders and the number of independently phase shiftable camshafts in the engine. Each sensing tooth is associated with one of the engine's cylinders and one cam wheel contains an extra cylinder identification tooth associated with a selected cylinder.

Abstract: A method of inferring and predicting engine torque uses a function of a speed/load table, air/fuel ratio and spark advance. The effects of the magnitudes of engine spark retard, rich or lean air/fuel ratios and exhaust gas recirculation are accounted for using a series of multipliers. Friction torque is accounted for through a speed/air charge table look-up.

Abstract: A returnless fuel delivery control system is disclosed which regulates fuel rail pressure at the level needed for precise control of fuel mass flow to fuel injectors at both normal and elevated engine temperatures. This regulation is accomplished by precisely controlling the speed of the fuel pump motor as a function of the projected fuel demand based on engine RPM and injector pulse width. The projection is modified as a function of differential pressure error. The differential pressure error responds to a fuel temperature strategy which increases the target differential pressure as a function of fuel temperature.

Abstract: Auxiliary control is used to reduce the processing load of an engine control computer by directly controlling a fuel injection system of an internal combustion engine. After initial set up, an auxiliary controller is able to control up to eight injectors while only receiving delay times from engine operating events, e.g. power stroke of each associated cylinder, and pulse width time periods defining the activation times for the injectors. The auxiliary controller can also maintain limited engine operation in the event of failure of the engine control computer when the computer is unable to provide updated delay times and pulse width time periods. A delay time and a pulse width time period are continuously calculated by the engine control computer and provided to the auxiliary controller. The most recently received delay time and pulse width time period are then used by the auxiliary controller to control up to eight identified fuel injectors.

Abstract: A method and system are provided for modifying a control signal of a fuel injector of a fuel delivery system wherein at least one shut-down temperature signal representing the temperature of an internal combustion engine is utilized together with other input signals to calculate a net amount of heat transferred to the fuel delivery system. The signals are utilized to calculate a correction factor, which correction is used to modify the control signal for the fuel injector. Preferably, two shut-down temperature signals are utilized, an engine coolant shut-down temperature signal and an air charge shut-down temperature signal to calculate the net amount of heat transferred. The modified control signal provides accurate control of the fuel injector by compensating for the increased volatility of the heated liquid fuel.

Abstract: A semiconductor accelerometer having a sensor element supported by a pedestal coupled to a substrate. Coupling between the pedestal and the sensor element includes opposing torsion beams along the axis of flexure coupled through a spring to the pedestal. The spring includes a pair of beams extending in a direction perpendicular to the torsion beams so that thermal expansion applies a tensile force to the torsion beams.

Abstract: A method of making a unitary spark distribution cassette involves molding a cassette and placing electrically conductive lead frames within the cassette during molding. Electrically conductive sleeves for fitting over spark plugs are also provided on the cassette. An ignition system circuit using high voltage diodes in conjunction with an alternating flux ignition coil is placed in the cassette and connected to the lead frames and the sleeves to create a complete electrical circuit. The cassette is then filled with epoxy resin to encase the electrical components to form a unitary package.

Abstract: A variable cam phase timing system in which there is one crankshaft sensor, and one camshaft sensor per independently phase shiftable camshaft which can be used for controlling the cam phase shifting, sequential fuel control, and also spark timing during both start-up and during run. In addition, the system can control spark timing, without phase shifting, should the crankshaft sensor fail.

Abstract: This invention teaches a system for interrupting operation of the internal combustion engine of a vehicle so as to prevent an undesirably high level of carbon monoxide in the ambient by using the voltage output signal from an engine oxygen sensor placed in the exhaust stream. Engine operation is interrupted when there are simultaneous signals indicating both an EGO sensor signal level above a predetermined value and idling condition of the engine.

Abstract: A flow sensor which includes a support structure including a base having a plurality of spaced mesas on a surface thereof is provided. A low thermal conductivity, dielectric diaphragm spanning the mesas is supported along its length thereby and forms an electrical and thermal insulation barrier over the support structure and the mesas. At least one flow sensing element is superposed on the diaphragm so that the flow sensing element is substantially electrically and thermally isolated from the support structure. A method for fabricating the flow sensor is also provided.

Abstract: A multiple entry air intake passage for a heating and air conditioning system has a first inlet for receiving fresh air and a second inlet for receiving recirculation air, the second inlet having two distinct openings in two walls of the passage housing for increasing the flow of air into the system. An L-shaped damper door has a main portion disposed to seal a main opening of the second inlet, and an auxiliary portion disposed to seal an auxiliary opening of the second inlet. The L-shaped damper door is pivotally mounted onto the housing of the air intake passage to allow pivoting movement between the fresh air and recirculation air positions.

Abstract: A hot-wire mass air flow sensor includes integral, elongated silicon members with a silicon dioxide coating on which temperature sensitive resistors are deposited. The air flow sensor has an extremely low thermal conductivity material base on which is mounted one or more of the elongate silicon members. This structure maximizes the thermal impedance of the conductive path existing at the ends of the flow sensor resistors and minimizes sensor errors. A method for fabricating the air flow sensor is also provided.

Abstract: This invention teaches a system for interrupting operation of the internal combustion engine of a vehicle so as to prevent an undesirably high level of carbon monoxide which would cause a low level of oxygen in the ambient. Engine operation is interrupted when there are simultaneous signals indicating an oxygen level below a predetermined value and an idling condition of the engine.

Abstract: This invention teaches a system for interrupting operation of the internal combustion engine of a vehicle so as to prevent an undesirably high level of carbon monoxide in the ambient. Engine operation is interrupted when there are simultaneous signals indicating a carbon monoxide level above a predetermined value and and idling condition of the engine.

Abstract: A plurality of first accelerometers are positioned forward of the passenger compartment and interconnected between vehicular ground and an airbag ignitor. At least one second accelerometer is positioned with the passenger compartment and electrically connected in series between the airbag ignitor and a reserve source of electrical power thereby providing a first firing path. Electronic circuitry positioned within the passenger compartment and connected to the airbag ignitor provides a second firing path through the ignitor to a passenger compartment ground independent of the vehicular ground which the first accelerometers are connected. This second conductive path is provided for a predetermined or dwell time in response to actuation by any of the first accelerometers. The electrical circuitry also includes prefiltering circuitry.

Abstract: The method for determining a fault in an exhaust gas recirculation system includes comparing the measured exhaust gas flow of the EGR system to an expected exhaust gas recirculation flow. If the two are not the same the time period that the expected exhaust gas recirculation flow deviates from the measured exhaust gas recirculation flow by a calibrated EGR flow amount is determined. A fault condition in the EGR system is indicated if the duration of the deviation exceeds a predetermined amount of time.

Abstract: A plastic molded fuel rail includes a plurality of core fuel injector assemblies molded within the fuel rail. Each core fuel injector assembly includes a magnetic core, electrical coil bobbin having electrical contacts extending therefrom, and axial fuel passageway. The magnetic core, coil bobbin assembly, and electrical contacts are hermetically sealed from the fuel passageways. An armature and sleeve including a needle and seat valve are inserted into the core fuel injector assemblies to provide fuel injectors. Trimming resistors are appropriately selected connected in series between each fuel injector and a corresponding electronic driver to achieve substantially uniform fuel flow through each fuel injector of the fuel rail.

Abstract: A fuel injector having major components formed by an injection molding process. A coil bobbin assembly is positioned within a magnetic permeable core. An injection molding process provides a plastic housing with the magnetic core and coil bobbin assembly hermetically sealed therein. The molding process also provides a fuel passageway through, and hermetically sealed from, the magnetic core and coil bobbin assembly.