Abstract: Fuel-vapor evaporating from a fuel tank is led though a vapor pipe and absorbed in a charcoal canister. Though the evaporating rate is influenced by the altitude where the automobile operates, the air-fuel ratio must be controlled within the proper range. This apparatus controls a purge valve in accordance with the purge rate which is determined based on the standard atmospheric pressure and compensated in accordance with the present atmospheric pressure. Therefore, this apparatus can precisely control the amount of purged fuel and the air-fuel ratio.

Abstract: Fuel-vapor evaporating from a fuel tank is led through a vapor pipe and absorbed in a charcoal canister. Fuel-vapor stored in the charcoal canister is supplied to an inlet pipe when a purge valve is opened when the engine is driven, because the pressure in the inlet pipe is low. Fuel-vapor is then burned as fuel in the engine. If the opening of the purge valve is suddenly increased at the start of the purge, the air fuel ratio control is disturbed. Therefore, the purge rate is gradually increased and the vapor concentration of the fuel-vapor purged from the charcoal canister is learned, and the change rate of the purge rate is made small because the air-fuel ratio control may be disturbed when the vapor concentration is not learned enough.

Abstract: A purge amount is estimated by taking the change of purge amounts of a vapor from a canister side and a fuel tank side into consideration, an amount of fuel injection is corrected by the purge amount so estimated, and air-fuel ratio control is executed with a high level of accuracy. In an apparatus for correcting an amount of fuel injection of an internal combustion engine for purging the vapor directly evaporating from the fuel tank and the vapor emitted from the canister into an intake passage through a solenoid control valve and executing an air-fuel ratio control on the basis of the total purge flow amount, a correction amount of the amount of fuel injection on the tank side, which changes with the vapor supplied directly from the fuel tank into the intake passage through the control valve is calculated and a correction amount of fuel injection on the canister side which changes by the vapor supplied from the canister to the intake passage through the control valve is calculated.

Abstract: An air-fuel ratio control apparatus includes: a determining part for determining a target purge ratio in accordance with operating conditions of an engine; a purge control part for controlling a flow rate of evaporated fuel, supplied from an evaporated fuel purge system into an intake passage of the engine, by actuating a purge control valve based on the target purge ratio, and for storing an evaporated fuel flow rate of the purge control valve; a fuel injection control part for generating a drive signal in accordance with a fuel injection time, and for controlling an air-fuel ratio of an air-fuel mixture to the intake passage by actuating a fuel injection valve in accordance with the drive signal; an estimating part for estimating the ratio of an evaporated fuel flow rate to an intake air flow rate based on sensed operating conditions of the engine and on the stored evaporated fuel flow rate of the purge control part; and a fuel injection time determining part for determining a fuel injection time based on t

Abstract: An evaporated fuel control apparatus includes a fuel tank for storing fuel, a first passage for connecting an internal space of the fuel tank to the atmosphere, the first passage having an opening which is open to the atmosphere, and a fuel vapor separating unit provided in the first passage for separating evaporated fuel of the fuel tank from air fed from the fuel tank to the atmosphere via the fuel vapor separating unit, the fuel vapor separating unit permitting passage of molecular components of air and not permitting passage of molecular components of fuel.

Abstract: An evaporated fuel purge control apparatus includes a purge control valve arranged in a purge passage between a canister and an intake passage of an engine, the purge control valve being switched on and off in accordance with a control factor, the control factor indicating a duty ratio of an on-time of the purge control valve within a duty cycle to a total duty-cycle time, a detecting part for detecting an operating condition under which the engine is operating, and a flow rate control part for setting a control factor for the purge control valve in accordance with the operating condition detected by the detecting part, the control factor set by the flow rate control part allowing a flow rate of evaporated fuel fed from the canister into the intake passage through the purge control valve to be maintained at a constant level when the operating condition of the engine changes.

Abstract: A fuel pressure control apparatus includes a valve for controlling an internal pressure of a fuel tank, the valve including a valving member, a valve seat, and an actuating member for pressing the valving member on the valve seat under a set pressure; and a pressure adjusting part for adjusting the set pressure of the actuating member of the valve to a first set pressure when an engine is operating, the first set pressure being higher than an atmospheric pressure and allowing the internal pressure of the fuel tank to be in equilibrium with the first set pressure, and for adjusting the set pressure of the actuating member to a second set pressure when the engine stops operating, the second set pressure being higher than the first set pressure, thus allowing the internal pressure of the fuel tank to be increased, when the engine stops operating, to a pressure higher than the first set pressure.

Abstract: An apparatus for controlling a flow of evaporated fuel from a canister being fed into an intake passage of an engine through a plurality of control valves arranged in parallel in a purge passage between the canister and the intake passage. The plurality of control valves includes at least a first valve being switched on and off by setting a control factor indicating a duty ratio of an on-time within a duty cycle to a total duty-cycle time for the first valve, and a second valve being switched on and off by setting a control factor indicating an on-state or off-state of the second valve for a total duty-cycle time. The apparatus includes a first control part for setting a first control factor for the first valve so that the first valve is switched on at a rate indicated by the first control factor, and a second control part for setting a second control factor for the second valve so that the second valve is switched on and off at a timing different from a timing at which the first valve is switched on and off.

Abstract: A device for controlling a fuel evaporative purge system having a solenoid valve arranged in a purge passage, comprises a unit for determining a maximum amount of fuel vapor to be purged, an air flow meter, a unit for calculating a maximum purging ratio of the maximum amount of fuel vapor to an amount of intake air, a unit for setting a purging ratio which is gradually varied during the purging process, and a unit for activating the solenoid valve. In the purging operation, the activating unit drives the valve at a duty-ratio identical to a ratio of the purging ratio to the maximum purging ratio.

Abstract: A malfunction detection apparatus for detecting a malfunction in an evaporative fuel purge system, which malfunction detection apparatus is able to suppress a fluctuation of an air-fuel ratio. A negative pressure inside an intake passage is introduced into the evaporative fuel purge system. The existence/nonexistence of a malfunction in the evaporative fuel purge system is determined by using pressure values inside the evaporative fuel purge system which values are detected and supplied by a pressure detecting unit. The apparatus is provided with an air-fuel ratio fluctuation suppressing unit for suppressing a fluctuation of the air-fuel ratio of air suctioned into an engine when introducing the negative pressure into the evaporative fuel purge system.

Abstract: An evaporative fuel control system able to control an air-fuel ratio of an engine to be a stoichiometric air-fuel ratio while a purge of evaporative fuel is executed The system comprises a microcomputer for computing a target flow amount of evaporative fuel gas to be purged into an intake line via a solenoid valve in accordance with signals from a volume detecting sensor, a fuel temperature detecting sensor, and an air flow detecting sensor; the micro computer also serving for computing a fuel vapor amount contained in the target flow amount. An air flow amount contained in the target flow amount of evaporative fuel gas purged into the intake line is computed by the microcomputer in accordance with the fuel vapor amount therein. A correction amount of fuel to be injected into the intake line is controlled so as to obtain a stoichiometric air-fuel ratio in various conditions of the engine.

Abstract: A pressure control device allows evaporated fuel evaporated in an fuel tank of an engine to be discharged to a canister during the engine running state. The canister absorbs the evaporated fuel. The pressure control device continues to allow evaporated fuel in the fuel tank to be discharged to the canister after the engine stops until a predetermined period has elapsed. The pressure control device allows evaporated fuel in the fuel tank to be discharged to the canister while a pressure in the fuel tank is higher than a first predetermined pressure after the predetermined period has elapsed in the engine stopped state. On the other hand, the pressure control device prevents evaporated fuel in the fuel tank from being discharged to the canister while a pressure in the fuel tank is lower than the first predetermined pressure after the predetermined period has elapsed in the engine stopped state.

Abstract: A fuel supply control device including a purge control valve. The maximum purge rate, that is, the ratio between the amount of purge and the amount of intake air when the purge control valve is fully open, is stored in advance. The purge control valve is controlled in its duty ratio, which duty ratio is the target purge rate/maximum purge rate. When the purge is started, the target duty ratio is gradually increased. When the purge is performed and the feedback correction coefficient FAF falls, the feedback correction coefficient FAF is gradually returned to the FAF before the start of a purge, the purge A/F correction coefficient is increased, and the amount of injection is corrected by the sum of the purge A/F correction coefficient and the feedback correction coefficient.

Abstract: A continuously variable transmission (CVT) used in a vehicle is controlled such that an actual engine speed Ne is equalized to a desired engine speed Ne'. A reference engine speed Ner is defined to be nearly equal to and less than Ne'. When Ne<Ner, or Ne>Ne', the speed ratio e of the CVT is allowed to be changed, while the change is inhibited when Ner.ltoreq.Ne<Ne'.

Abstract: In a control device in continuously variable transmission system for a vehicle, wherein a belt is racked across a pulley on the input side and a pulley on the output side, an engine power is transmitted through this belt, and an urging force of the belt by one of the pulleys is controlled by a line pressure of a hydraulic cylinder of the pulley, an engine output torque is determined from an engine rotational speed, an intake throttle opening or an intake air flowrate per unit rotation of the engine and engine operation parameters other than said data, and the line pressure is regulated in relation to the so determined value to obtain the proper line pressure as accurately commensurate to the actual output torque of the engine, so that the fuel consumption rate can be lowered to the maximum, avoiding the slips of the belt.

Abstract: A method for controlling a continuously variable transmission installed in a vehicle. The method utilizes a changing rate for varying a RPM ratio between an output shaft and an input shaft to compensate for large and small throttle openings as well as varying rates of changing the throttle opening.

Abstract: In a device for performing the control during acceleration in a continuously variable transmission system for a vehicle, wherein a speed ratio e of the continuously variable transmission system is controlled such that an actual engine rotational speed Ne can be a target engine rotational speed Ne', a predetermined value Nb lower than Ne' and a predetermined vale N.times.3 slightly higher than Nb are set, the shift in the continuously variable transmission system is interrupted until Ne is increased to a predetermined value higher than Ne' when Ne enters a state of Nb<Ne.ltoreq.N.times.3, and the speed ratio e of the continuously variable transmission system is continuously raised until Ne is decreased to a state of Ne.ltoreq.N.times.3 when Ne is changed from a state of Ne>Ne' to a state of Ne<Ne', so that the device can maintain a satisfactory acceleration, suppress the decline of a transmission efficiency and reduce the noise level during acceleration.

Abstract: In a control device in a continuously variable transmission system for a vehicle, wherein the continuously variable transmission system is provided on a power transmission route of an engine and a speed ratio thereof is controlled such that an engine rotational speed can be a target engine rotational speed, when a detected acceleration during acceleration is smaller in value than the reference acceleration or a detected deceleration during deceleration is smaller in value than the reference deceleration, the transient time target engine rotational speed is selected instead of the steady time target engine rotational speed, whereby a speed ratio of the continuously variable transmission system is made to be a small value during acceleration and deceleration.

Abstract: Method and apparatus for controlling a continuously variable transmission operatively connecting an engine and drive wheels of a vehicle, wherein a speed ratio of the transmission is controlled such that an actual engine speed coincides with a target engine speed.

Abstract: Method and apparatus for controlling a continuously variable transmission operatively connecting an engine and drive wheels of a vehicle, wherein a speed ratio of the transmission is controlled such that an actual engine speed coincides with a target engine speed.