Abstract: An air-fuel ratio control apparatus of an internal combustion engine controls the change in the amount of fuel discharged into an intake passage downstream of a throttle valve of the engine more smoothly in accordance with the change in the amount of fuel discharged into the intake passage upstream of the throttle valve. Thus, the air-fuel ratio of the air-fuel mixture fed into the cylinder of the engine is changed smoothly without causing a surging phenomenon to occur in the engine.

Abstract: An engine rotation speed control system for automotive vehicles having internal combustion engines comprises a solenoid actuated valve having a solenoid coil for controling the flow of air through a throttle bypass passage to the intake manifold during engine idling upon energization of the solenoid coil. The electrical circuit for the solenoid coil is provided with a variable resistance arrangement so that sufficient current will be supplied to the solenoid coil upon engine starting in spite of a voltage drop in the battery at cold temperatures.

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.

Abstract: An automotive type carburetor is provided with a choke construction that assures opening of the choke valve without the use of vacuum in the event of an electrical failure in the choke assembly, or a failure in the secondary air pump system of the engine; the choke housing being supplied with hot air under pressure from the engine secondary air pump to warm the choke bimetal, the choke assembly also including a PTC heater element to independently warm the bimetal, either heating means being adequate to assure opening of the choke valve within a desired time in the event of a failure of the other heating means.

Abstract: An electronic fuel injection system is provided with a closed loop control having a plurality of loops for proportioning a mixture of air and fuel delivered to an internal combustion engine. The system has a sensor for providing an electrical signal, the magnitude of which varies in proportion to the concentration of a constituent of exhaust gas from the engine. A first of the loops compensates for small amplitude, short term disturbances of said signal. The second loop compensates for large amplitude, long term signal disturbances. Signals from the first and second loops are combined to produce a composite signal that maintains precise control over the average air/fuel ratio while generating rapid small amplitude fluctuations in that air/fuel ratio which shortens the response time of the system and increases its ability to reduce exhaust gas pollutants.

Abstract: A carbureting type fuel metering apparatus has an induction passage into which fuel is fed by several fuel metering systems among which are a main fuel metering system and an idle fuel metering system, as generally known in the art; engine exhaust gas analyzing means sensitive to selected constituents of such exhaust gas creates feedback signal means which through associated solenoid transducer means become effective for controllably modulating the metering characteristics of the main fuel metering system, and, if desired, the idle fuel metering system as to thereby achieve the then desired optimum metering functions.

Abstract: Disclosed ia an air-fuel ratio control method and apparatus of an internal combustion engine. The control of the air-fuel ratio is accomplished by controlling the amount of fuel provided into the engine according to a plurality of separate electrical engine condition signals which indicate the operating condition of the engine, and according to an electrical air-fuel ratio correction signal which is determined in accordance with the air-fuel ratio of the engine. The value of at least one of the engine condition signals is corrected according to a signal which indicates a mean value of the air-fuel ratio correction signal. The correcting operation is executed so that the value of the mean value signal becomes nearly equal to a predetermined value which corresponds to the air-fuel ratio correction signal when a desired air-fuel ratio is obtained.

Abstract: A fuel metering apparatus is shown as having a throttle body with an induction passage therethrough and a throttle valve for controlling flow through the induction passage, a fuel-air mixture discharge member is situated generally in the induction passage downstream of the throttle valve, an air passage communicates between a source of air and the fuel-air mixture discharge member, the air passage also includes a flow restrictor therein which provides for sonic flow therethrough, and a fuel metering valving assembly is effective for metering liquid fuel at a superatmospheric pressure and delivering such metered liquid fuel into the air passage upstream of the flow restrictor thereby causing the thusly metered liquid fuel and air to pass through the sonic flow restrictor before being discharged into the induction passage by the fuel-air mixture discharge member.

Abstract: An air-fuel ratio control device characterized by the fact that an electromagnetic valve which controls the air bleed quantities for both high- and low-speed fuel systems simultaneously has a pin inserted in a valve disc so as to prevent the rotation of the valve disc but allow it to move axially for open-close operation, so that the valve disc and the seat always contact at the same contacting portion and maintain a perfect seal therebetween. This enables an accurate control of the air bleed quantitiy and therefore of the air-fuel ratio.

Abstract: An altitude compensation device for an internal combustion engine having a vacuum-operated ignition timing advancer and a carburetor has an atmospheric pressure variation responsive valve operative to control the air bleed of the carburetor and the vacuum fed to the vacuum advancer such that, as the atmospheric air pressure is lowered due to increase of the altitude, the air flow into the advancer vacuum chamber is decreased to advance the ignition timing while the air flow into the carburetor air bleed passage is increased to increase the air-fuel ratio of the air-fuel mixture produced by the carburetor.

Abstract: A carburetor choke plate is rotated by a driver in one direction from its wide open position for cold enrichment and in the opposite direction from its wide open position for stoichiometric air-fuel ratio control. A fast idle cam limits throttle closure during operation in the cold enrichment mode, and a stop limits movement of the main metering rod toward its rich position in the stoichiometric air-fuel ratio control mode. The choke mechanism also positions an idle bleed valve to vary idle air-fuel ratio, and controls a latch to prevent secondary operation, during both the cold enrichment and the stoichiometric air-fuel ratio control modes.

Abstract: A feedback type air fuel ratio controlling system for detecting and controlling an exhaust gas composition of an engine. A gas sensor provides a sensor signal related to an exhaust gas concentration. This sensor signal is coupled through an automatic gain control (AGC) DC level amplifier to a deviation detector. The deviation detector compares the signal to a reference signal V.sub.p representing a stoichiometric air fuel mixture and provides a correction signal for adjusting the engine's air fuel ratio. The AGC DC level amplifier provides automatic DC level compensation for a slowly deteriorating sensor and, working in combination with the deviation detector, an AC hysteresis response for judging rich to lean and lean to rich changes sensed by the exhaust gas sensor.

Abstract: A method and apparatus for controlling the various functions of an internal combustion engine using a program-controlled microprocessor having a memory preprogrammed with various control laws and associated control schedules receives information concerning one or more engine-operating parameters such as manifold pressure, throttle position, engine coolant temperature, air temperature, and engine speed or period and the like. These parameters are sensed or measured and then the value thereof is supplied to input circuits for signal conditioning and conversion to digital words usable by the microprocessor.

Abstract: A closed loop fuel controller for a vehicle internal combustion engine is responsive to the oxidizing/reducing conditions in the exhaust gases from the engine to provide a control signal for adjusting an air and fuel supply means and which varies in a sense tending to produce a predetermined air/fuel ratio. When the engine operation changes from one condition to another condition representing an acceleration or deceleration transient, the value of the air/fuel supply adjustment is preset to a value from a memory location addressed by the engine condition determined to produce the predetermined air/fuel ratio when the engine is accelerating and to a value from another memory location addressed by the engine condition determined to produce the predetermined air/fuel ratio when the engine is decelerating so that the air/fuel ratio adjustment is substantially instantaneously preset to the value determined to produce the predetermined ratio during engine accelerating and decelerating transient conditions.

Abstract: An electronic injection carburetor is disclosed. Fuel under pressure is quantized for primary metering by an electronic fuel injector and input to a metered fuel chamber. The quantization occurs by controlling the duration of the opening time of the injector by an electronic control unit responsive to speed and manifold absolute pressure information. Secondary metering is provided as a function of the mass air flow through the throat of the carburetor by an actuator assembly controlling fuel input to the carburetor from the metered chamber. The actuator provides the secondary metering by changing the bias pressure on a flexible diaphragm producing a closure force on a needle valve that varies the flow of fuel from the metered chamber to an atomizing discharge nozzle in the throat of the carburetor.

Abstract: In a carburetor for an internal combustion engine, a control valve is disposed with an air passage through the carburetor structure to control the flow quantity of air to be mixed with fuel from a float chamber and a pneumatic servo-motor is operatively connected with the control valve to control the opening degree of the valve. The pneumatic pressure applied to the servo-motor is electrically controlled to satisfy the following function in relation to the engine intake manifold vacuum and the engine speed.Pd=f(Pv, N)where the character Pd is the pneumatic pressure applied to the servo-motor, and the characters Pv and N respectively indicate the engine intake manifold vacuum and the engine speed.

Abstract: A carburetor for combustion engines with a mixing chamber in the carburetor housing, the mixing chamber being bounded downstream by a randomly actuated mixture throttle and upstream by an air throttle controlling the intake air cross section and actuated by the pressure prevailing in the mixing chamber. A bypass air duct discharges into the center of the mixing chamber and receives the fuel supply. A nozzle pin cooperates with the air throttle and controls the cross section of a fuel jet. Downstream of this jet is another fuel jet whose cross section is controllable as a function of engine operating parameters by means of an analog magnet. The fuel jet controlled by the analog magnet may be the fuel outlet in the bypass air duct, and may be controlled by a nozzle pin through a lever via the analog magnet which is a plunger system. The second fuel jet may be located in a bypass air duct and its cross section may also be controlled by an analog magnet as a function of engine operating parameters.

Abstract: An air-fuel ratio feedback control apparatus of an internal combustion engine in which an air-fuel ratio of an air-fuel mixture is at first set on the lean side of the desired air-fuel ratio. Additional fuel is supplied from at least one fuel injection valve. The amount of injected fuel each time the injecting operation is carried out is increased or decreased by a certain quantity in accordance with an air-fuel ratio condition signal detected by an air-fuel ratio sensor. Only when the air-fuel ratio feedback, control operation is initiated, then is a large amount of fuel abruptly supplied to the engine by an auxiliary fuel control means. Thereafter, the normal injecting operation is carried out together with the operation for increasing or decreasing the amount of injected fuel by a certain quantity.

Abstract: A carbureting type fuel metering apparatus has an induction passage into which fuel is fed by several fuel metering systems among which are a main fuel metering system and an idle fuel metering system, as generally known in the art; engine exhaust gas analyzing means sensitive to selected constituents of such exhaust gas creates feedback signal means which through associated transducer means become effective for controllably modulating the metering characteristics of the main fuel metering system and the idle fuel metering system.

Abstract: This invention relates to a computer controlled fuel system for an internal combustion engine including a low profile carburetor for permitting engine operation on very lean fuel/air ratios without sacrificing engine performance during critical engine operations such as start up, warm-up and acceleration. The low profile carburetor provides a single point source fuel dispersion and includes one or more throttle controlled, sliding plates for increasing fuel entrainment at low engine speeds by increasing the velocity of the airstream flow through the carburetor just before the dispersion point and by maximizing the lateral distance between the point of fuel dispersion and the carburetor airstream. The computer controlled system includes various threshold circuits for providing additional fuel and/or water injection into the carburetor airstream upon detection of predetermined engine conditions.

Abstract: A circuit means in combination with a conventional oxygen ion conductive solid electrolyte cell establishes the cell in a voltage mode for the purposes of measuring excess oxygen and developing a voltage signal indicative thereof, and switching the cell to a current mode of operation in response to an excess combustible environment wherein current drawn by the cell to pump oxygen for combustible reaction with the excess combustibles environment is measured as an indication of the combustibles content of the gas.

Abstract: An electro-mechanical cartridge type fuel flow control valve assembly that can be substituted as a whole for the conventional power valve unit of a carburetor to convert the carburetor to one of the feedback type. The cartridge includes a stepper motor threadedly engaging a needle like power valve for vertically moving the power valve to vary fuel flow upon energization of any of four terminals formed as a quick disconnect coupling as part of the cartridge.

Abstract: A carbureting type fuel metering apparatus has an induction passage into which fuel is fed by several fuel metering systems among which are a main fuel metering system and an idle fuel metering system, as generally known in the art; engine exhaust gas analyzing means sensitive to selected constituents of such exhaust gas creates feedback signal means which through associated transducer means become effective for controllably modulating the metering characteristics of the main fuel metering system and the idle fuel metering system.

Abstract: A carbureting type fuel metering apparatus has an induction passage into which fuel is fed by several fuel metering systems among which are a main fuel metering system and an idle fuel metering system, as generally known in the art; engine exhaust gas analyzing means sensitive to selected constituents of such exhaust gas creates feedback signal means which through associated transducer means become effective for controllably modulating the metering characteristics of the main fuel metering system and the idle fuel metering system; reciprocating type solenoid control valve means is employed for modulating actuating pressure applied to the structure of the main fuel metering system and idle fuel metering system in order to achieve the desired metering functions.

Abstract: A method for decreasing CO and HC emissions in a vehicle exhaust stream during the period of engine warm-up following the start of engine operation, in which the A/F mixture to the engine is pulsed by first using a mixture which is leaner than that otherwise used thus reducing the CO and HC content of the exhaust stream exiting the engine to an amount below that of the CO and HC otherwise present and then using an A/F mixture which is richer than such lean mixture and is substantially that otherwise used thus increasing the amount of CO and HC in the vehicle exhaust stream to substantially the amount otherwise present, passing the pulsed exhaust stream through a catalytic converter adapted to oxidize the CO and HC constituents, and repeating this pulsing continuously through the period of engine warm-up and at a rate sufficient to achieve increased catalytic conversion of CO and HC over that obtained without pulsing, the rate being also sufficiently rapid so as to preclude engine-stall.

Abstract: A part of an engine air-fuel mixture is admitted from the intake passageway into a space and is burned to produce combustion gases for sensing the air-fuel ratio of the admitted air-fuel mixture and for controlling the air-fuel ratio of an engine air-fuel mixture in accordance with the sensed air-fuel ratio and exhaust gases resulting from the combustion gases are fed into the intake passageway.

Abstract: An air-to-fuel ratio control apparatus for a combustion engine which attains the combustion on combustible mixture in the engine cylinder to rotate the engine output shaft. A piezoelectric pressure detector secured to the combustion engine detects a pressure in the engine cylinder and three rotational position detectors respectively detect a first, second and third rotational positions of the engine output shaft. The second rotational position is determined to be intermediate between the first and third rotational positions and correspond to the transition point from compression to power strokes of the combustion engine. An electronic circuit compares a portion of and another portion of a pressure signal produced by the pressure detector during respective rotational intervals determined by the first and second rotational positions and by the second and third rotational positions to discriminate whether the combustion engine attained a complete combustion or not.

Abstract: A concentration cell comprising an electrolyte with two surfaces respectively covered with two metallic electrodes is partially mantled by a layer of an oxidizing catalyst. Heating means is disposed in the catalyst for heating it when electrically energized.

Abstract: An electronic control unit for regulating the air/fuel ratio of an internal combustion engine is disclosed. The electronic control unit has an open loop calibration for regulating air/fuel ratio that is corrected with a closed loop signal developed by an integral controller. The integral controller bases the closed loop correction signal on a signal from an exhaust gas composition sensor located in the engine exhaust manifold. Various conditions of the system are sensed by a closed loop sensor condition detector to provide information on whether the sensor is up to operating temperature and is operative. If the exhaust gas sensor is functioning and the operating system parameters indicate the system operation should move to closed loop control, the loop is closed by the condition detector. Included in the condition detector circuit is a timer whose cycle is RPM dependent.

Abstract: An electronic control unit for regulating the air/fuel ratio of an internal combustion engine is disclosed. The electronic control unit includes an injector driver circuit which regulates the timing of the opening and closing operations of a plurality of electromagnetic solenoid injectors which input fuel to the engine. The injector driver circuit controls the injection with a pulse width modulated signal to supply an amount of fuel calculated from the operating parameters of the engine. The injector driver circuit is further provided with an energy dissipation circuit to assist in the rapid de-energization of the solenoid injectors. The energy dissipation circuit drains the energy stored in the rapidly collapsing magnetic field of a de-energized injector through a power device whose energy dissipation is controlled by the breakdown voltage of a Zener diode connected to the control terminal of the power device.