Abstract: A method of, and an apparatus for, controlling fuel injection in an internal combustion engine prevent lean misfires and a discharge of unburned HC at and after the start of the engine.The apparatus has a drive circuit 50 for opening a fuel injector 12 of each cylinder at predetermined crank angles, a unit A for determining whether or not the speed of the engine is above a reference speed, a unit B for determining whether or not fuel in a cranking quantity has been injected into every cylinder of the engine, and a switching unit C for switching the quantity of fuel to be injected from the cranking quantity to a post-cranking quantity if the unit A determines that the engine speed is above the reference speed and the unit B determines that fuel in the cranking quantity has been injected into every cylinder.
Abstract: An amplifier circuit employs a differential amplifier having first and second differential inputs and having an output for providing an output signal which varies according to a difference between magnitudes of input signals provided at the first and second inputs, a high impedance front end which is coupled to the first input of said differential amplifier and which accepts an input voltage, and a feedback circuit which is interposed between the second input and the output of the differential amplifier so that error characteristics of the feedback circuit are substantially similar to error characteristics of the front end and signal errors introduced by the high impedance front end are canceled by signal errors provided by the feedback circuit. The differential amplifier can be an operational amplifier and the high impedance front ends and the feedback circuits can be source follower FET circuits each having an FET transistor and a resistor connected to the source terminal of said FET transistor.
Abstract: A connection part for an ignition device, arranged between an ignition coil and a spark plug for incorporating in a cylinder head of an internal combustion engine, has an isolation housing, a high voltage switching element located in the isolation housing and during application of a trigger voltage is transferred reversibly in an electrically jump-like fashion to an electrically conductive condition, a first junction element located at one end of the high voltage switching element and connected with one pole of the latter and also connectable with a high voltage terminal of the ignition coil which leads to an output voltage of the ignition coil, a second junction element provided at another end of the high voltage switching element and connected with another pole of the latter and provided for receiving a terminal pin of the spark plug, and an element associated with the isolation housing for increasing a capacity region between the high voltage switching element and the first junction element.
August 25, 1993
Date of Patent:
December 6, 1994
Robert Bosch GmbH
Walter Benedikt, Werner Herden, Manfred Vogel
Abstract: An engine control valve is disclosed which comprises a first bypass passage for introducing auxiliary air flow to an engine from an upstream side of an intake throttle valve disposed in an air intake pipe of the engine while bypassing the intake throttle valve; a second bypass passage having an inlet port in communication with an outlet port of the first bypass passage, for introducing the auxiliary air flow, introduced through the inlet port, to a downstream side of the intake throttle valve; a valve body for changing an opening area of at least one of the outlet port of the first bypass passage and the inlet port of the second bypass passage, thereby adjusting an amount of the auxiliary air flow to be introduced from the upstream side to the downstream side of the intake throttle valve; and a drive unit for driving the valve body in accordance with a drive signal outputted from the control unit.
Abstract: An arrangement is disclosed for the apportioning if the idling air of internal-combustion engines having an adjustment motor for driving an adjusting member for changing a flow control cross-section and a supplementary device which can be actuated when the internal-combustion engine is rendered inoperative and is used for controlling the adjusting member into a minimum opening of the flow cross-section serving as an emergency cross-section. The supplementary device comprises two magnets arranged to mutually affect one another, one of the magnets being rendered essentially inoperative during the operation of the internal-combustion engine and thus during the operation of the arrangement.
Abstract: An air-fuel ratio detecting apparatus for an internal combustion engine of an automotive vehicle has an air-fuel ratio sensing element disposed in the exhaust manifold of the engine, an electric heater which heats the sensing element to above its activation temperature, and a controller which controls the heater output in accordance with the operating state of the engine, a target air-fuel ratio, and at least one parameter selected from the speed of the vehicle and a temperature parameter so as to maintain the temperature of the sensing element constant even when the exhaust gas temperature of the engine varies.
Abstract: An improved system and method for controlling an engine idling speed for an internal combustion engine are disclosed in which an electromagnetic valve for controlling fluid flow quantity passing through a bypass passage of an engine throttle valve is provided, a water jaket for circulating an engine cooling water is provided so as to surround a coil portion of the electromagnetic valve. The change characteristic of the fluid flow quantity for the electromagnetic valve is varied according to the engine cooling water temperature, and both an optimum target idling speed and feedback control coefficients in a control variable of an opening angle of the electromagnetic valve, i.e., a voltage duty ratio applied to the electromagnetic valve are varied according to the engine cooling water temperature.
Abstract: In a fuel control apparatus by which a basic fuel quantity T.sub.p is first calculated on the basis of a detected intake air flow rate Q and a detected engine speed N as T.sub.p =KQ/N (K: constant) and the calculated basic fuel quantity T.sub.p is corrected on the basis of a correction coefficient COEF related to various engine operating conditions (e.g. coolant temperature), air/fuel ratio feedback correction coefficient .alpha., and a battery voltage correction coefficient T.sub.s as T.sub.i =T.sub.p .times.COEF.times..alpha.+T.sub.s, when an engine is accelerated, an initial fuel increment coefficient KAC.sub.0 is determined on the basis of throttle opening rate and engine speed, and added to the correction coefficient as COEF+KAC.sub.0, and thereafter the initial fuel increment coefficient KAC.sub.0 is reduced at a small coefficient decrement rate DKAC.sub.1 at lower engine speed to prevent hesitation, but at a large coefficient decrement rate DKAC.sub.
Abstract: An idling engine speed controlling apparatus has a feed-back control system to regulate engine speed to a target speed such that a torque disturbance is directly detected to convert it into a signal so that an air-flow rate or ignition timing is controlled on the basis of the sum of the signal and a time-differential of the signal, or such that sub-feed-back compensation is given to the output end of a proportional and integral controller so that an amount of air flowing in a intake air conduit is compensated with the first-order-lag component or an amount of air is controlled in response to the first-order-lag component or the second-order-lag component or the sum of or the difference between these components, or such that an output from the proportional and integral controller or an output from the actuator is fed back to the input side of the controller so as to include a transfer function of the actuator through a detection circuit.
Abstract: An improved engine ignition system for a marine engine or the like, which provides reliable start-up capability and running protection. The system detects the actual rotational speed of the engine and provides an electrical signal that is proportional to the measured speed, and selectively advances the ignition timing characteristic, and also controls overall engine speed to prevent engine damage that may be caused by an overspeed condition. The system advances the ignition timing characteristic during warm-up until a predetermined temperature is achieved, and also advances the ignition timing characteristic for a predetermined time period during initial running. The system utilizes the power of the battery during start-up to supplement the power that is generated by the stator coil which normally supplies all of the necessary power for the control circuitry of the ignition system.
Abstract: An ignition apparatus of electronic distribution type for a multi-cylinder internal combustion engine, comprising a plurality of ignition circuits each having an ignition coil and a power switching element for one or two cylinders of a multi-cylinder internal combustion engine is disclosed in which the ignition circuits are arranged into a plurality of ignition systems each having at least two of the ignition circuits and a signal current-limiting circuit is provided for each of the ignition systems to control the currents flowing through the power switching elements of the associated ignition circuits.
Abstract: An apparatus for controlling an air-fuel ratio of a combustion engine with a memory device for storing correct values for air-fuel control in accordance with an intake condition of said combustion engine and a rotation speed of the same. In the apparatus, an air-fuel ratio represented by the exhaust gas composition of the internal combustion engine is sensed and the sensed value is integrated. When the integrated value from the integrator fails within a predetermined range of values, one of the correction values for the air-fuel ratio control is corrected in accordance with a current condition of the internal combustion engine. When the integrated value falls outside the predetermined range, the correction values are replaced by a predetermined reference value and an air-fuel ratio of mixture supplied to the combustion engine is controlled in accordance with the correction values for the air-fuel ratio stored.
Abstract: A fuel control system for an internal combustion engine in which the accelerator pedal is set by the operator and defines an air flow control variable which is applied to a control loop that actuates a servo motor or other suitable rotary means to set the relative position of an air flow control flap within the induction tube. The control loop attempts to maintain the position of the air flow flap in continuous correspondence with the accelerator pedal position. The actuating current for the final control element is used as one input datum for a stored data field. Another input variable to the data field is the actual position of the air flow valve or flap. The data field contains empirically obtained data relating these two variables with the prevailing air flow rate and generates an output signal that is used as the air flow rate signal in a control pulse generator. The control pulse generator also receives other signals related, for example, to temperature, engine speed, etc.
December 22, 1980
Date of Patent:
June 22, 1982
Robert Bosch GmbH
Eberhard Mausner, Johannes Brettschneider
Abstract: A fuel system for an internal combustion engine and comprising a housing having a first chamber of cylindrical cross-sectional configuration with an upper air inlet port open to an air door and a lower outlet port connected to the engine intake manifold, a cylindrical spool rotatably positioned in the first chamber and having opposed openings which align with the inlet and outlet ports when the spool is in a full open position, a second chamber provided in the housing open to the heat of the engine exhaust system and separated from the first chamber by a partition, a fuel heating envelope secured within the second chamber whereby the heat of the exhaust system surrounds the envelope for heating the interior thereof, a fuel jet extending into the fuel envelope for admitting a fuel thereto, a bleed air passageway provided in the housing for directing air from the exterior thereof to the interior of the fuel envelope, a fuel nozzle secured through the wall and having one end open to the interior of the fuel heat
Abstract: An i.c. engine fuel control system includes a closed loop roughness control, utilizing a roughness sensor circuit, an integrator which integrates the error between the roughness signal and a reference signal and modifies the fuel flow to the engine via a main fuel control with a variable frequency clock. During acceleration and deceleration the closed loop is interrupted by means of a circuit including two differentiators which are sensitive to throttle opening (speed demand) and actual speed respectively, and switches controlled by these differentiators.
Abstract: A system for controlling in a feedback control mode the air-fuel ratio of an air-fuel mixture to be supplied to an internal combustion engine in response to the deviation from a reference value, of an output of an exhaust sensor for sensing the concentration of a component of engine exhaust gas. The reference value is varied even during stopping of the feedback control due to an lowered engine temperature, thereby preventing an erroneous control. Additionally, the reference value and the value of a current flow to the exhaust sensor are varied immediately when the feedback control is stopped due to lowering in the engine temperature, thereby quickening the initiation of the feedback control.
Abstract: A fuel injection installation for internal combustion engines having a plurality of injection valves for supplying fuel to the engine. Each injection valve is sealed to fuel distributing line and to either the intake manifold of the engine, or to the cylinder head of the engine, by at least one O-ring, each O-ring being braced only in the radial direction. Each injection valve is fixed in an axial direction on the fuel distributing line by means of a fastening plate yielding in the radial direction and embodied as bracket-like, which is insertable through appropriately shaped recesses in each insertion nipple on the fuel distributing line and can be snapped into an annular groove of each injection valve. As a result, there is assured not only a secure connection between the fuel distributing line and the injection valves which compensates for axial clearances required for manufacture, but also rapid mounting or dismounting of the fuel injection installation.
Abstract: A fuel control system is provided for a spark-ignition internal combustion engine having a source of fuel and means for supplying the fuel from the fuel source and to the engine at variable flow rates. The fuel control method of the present invention is particularly suited for a reciprocating piston aircraft engine and is designed to minimize brake specific fuel consumption of the engine during operation at constant engine rotational speed and load but is capable of supplying additional fuel to the engine during transient operation, for example during an acceleration phase. In brief, when the engine is operating under constant engine rotational speed and load, an engine parameter, such as the exhaust gas temperature, which is correlated to the brake specific fuel consumption for the engine is iteratively sensed and compared to the previously determined value for this parameter.
Abstract: Apparatus for venting fuel vapors present in the fuel bowl of a carburetor for an internal combustion engine. A carburetor has at least one air passage through which air is drawn into the engine, a throttle valve positioned in the air passage and movable between an open and a closed position to control the flow of air therethrough, a fuel circuit by which fuel is delivered from the fuel bowl to the air passage for mixing with air passing therethrough, and means responsive to the movement of the throttle valve for controlling the quantity of fuel delivered through the fuel circuit. A fuel bowl cover has a vent through which fuel vapors discharge when the vent is open and a valve opens and closes the vent. A fuel pump supplies fuel from the fuel bowl to the air passage as the throttle valve opens and moves the valve to a vent opening position in response to the movement of the throttle valve. The pump is actuated as the throttle valve opens whereby the valve is opened and vapors in the fuel bowl are vented.
Abstract: In a closed loop air-fuel mixture control system for carburetor-equipped internal combustion engines, an exhaust gas sensor provides a feedback signal to a control unit where the signal is modified to meet the control characteristics of the closed loop. The modified feedback signal is converted into digital pulses whose width varies with the amplitude of the feedback signal. Additional air is supplied to the engine through an air bleed in accordance with the magnitude of the analog feedback signal to provide a coarse control of air-fuel ratio and in response to the digital pulses to provide a fine control of the ratio. The mixture is controlled in a wide range of ratios to eliminate the need for calibration which would be required for fitting the closed loop system to the time-varying characteristics of individual carburetors.