Abstract: An internal combustion engine, wherein fuel vapor adsorbed in a canister (22) is purged into a surge tank (13) through a purge control valve (28). A target value of the fuel vapor rate showing the ratio of the amount of fuel vapor in the purge gas to the amount of fuel injection is stored in advance. At least one of the amount of purge gas or the amount of fuel injection is controlled so that the fuel vapor rate becomes the target value.

Abstract: A fuel vapor purge system connects a fuel tank with a canister and collects fuel vapor generated in the fuel tank by the canister. The purge system purges the collected fuel vapor to an intake passage of an internal combustion engine through a purge passage. A change of pressure due to fuel vapor generation in the fuel tank is measured while the purge passage is sealed. The pressure in the purge passage is differentiated from the pressure outside the purge passage and the purge passage is sealed. In this state, a change of the pressure in the purge passage is measured. After measuring the amount of generated fuel vapor, a test for leakage in the purge passage is performed based on the change of pressure due to the fuel vapor generation when measuring changes of pressure in the purge passage during a predetermined period.

Abstract: An evaporative fuel leakage preventing device is designed such that an adsorbent is disposed in an intake passage so as to adsorb evaporative fuel generated in the intake passage during stoppage of the engine and prevent evaporative fuel from being discharged to the atmosphere. The device prevents evaporative fuel that has been previously adsorbed by the adsorbent, and that is desorbed from the adsorbent due to the ambient temperature while the engine is not in operation, from being emitted to the atmosphere even when the engine is not in operation.

Abstract: A lower wall (8) forming a fuel storage chamber (5) becomes curved downward according to increase of the fuel amount, and at this time a support member (23) for supporting the fuel storage chamber (5) does not restrain the downward curvature of the lower wall (8), whereby the capacity of the fuel storage chamber (5) can be increased and whereby the amount of the fuel that can be stored in the fuel storage chamber (5) can be maintained at the maximum, as compared with structure inhibiting deformation of the lower wall (8).

Abstract: A cylinder injection type lean-burn internal combustion engine is capable of executing the purging of a vapor fuel without disturbing a state of an air-fuel mixture in a combustion chamber. The vapor fuel produced in a fuel tank is guided to a purge port provided at an intake passageway of the lean-burn internal combustion engine, and subsequently supplied along an intake air swirl flow into the combustion chamber. The vapor fuel is thereby partially concentrated in any one of a combustible air-fuel mixture layer and an air layer in the combustion chamber.

Abstract: In an internal combustion engine in which a throttle valve is substantially fully opened in most of the operating regions such as an in-cylinder injection type internal combustion engine, a technique is provided capable of effectively processing an evaporative fuel while stabilizing a combustion state of the internal combustion engine even in the case that an amount of evaporative fuel generated in a fuel tank or the like is increased. To achieve this technique, a purge amount of evaporative fuel is increased by increasing a differential pressure between an upstream portion and a downstream portion of a purge passage, and the differential pressure between an upstream portion and a downstream portion of a purge passage, and the differential pressure is adjusted in accordance with the combustion state of the internal combustion engine at that time, thereby making it possible to purge the maximum amount of evaporative fuel within a range in which the combustion state is not unstabilized.

Abstract: A fuel vapor feed controlling apparatus of a lean burn internal combustion engine suppresses either one of a rich misfire or a surge when fuel vapor is fed into the engine. A purge controlling unit controls an amount of fuel vapor fed from a fuel reservoir to the engine in response to an operational condition of the engine. A first compensation unit compensates the amount of fuel vapor such that an engine revolution speed of the engine may be identical with a target revolution speed. The purge controlling unit performs a purge control based on a compensation value compensated by the first compensation unit.

Abstract: A fuel vapor control apparatus determines whether the concentration of fuel vapor in a space above the surface of liquid fuel in the fuel tank is less than a predetermined concentration. When the concentration of fuel vapor is less than the predetermined concentration, the concentration of fuel vapor in the fuel tank is increased and, when the concentration of fuel vapor exceeds the predetermined concentration, the increase of the concentration of fuel vapor is stopped. Therefore, an amount of fuel flowing out of the fuel tank can be reduced while using a reduced amount of energy.

Abstract: A diagnostic apparatus for a fuel storage device has a gas introducing passage for introducing gas from a fuel storage device into an intake passage of an internal combustion engine and a shutoff valve that shuts the gas introducing passage. The diagnostic apparatus detects an amount of fuel component introduced into the intake passage via the gas introducing passage when the shutoff valve is in at least one of an open state and a closed state on the basis of the detected amount of fuel component and, upon detecting the presence of the fuel component in the introduced gas, the apparatus diagnoses that the fuel storage device has a fault.

Abstract: According to the present invention, there is provided a device for diagnosing malfunction in a fuel tank. The fuel tank has a separator wall therein which separates an interior of the fuel tank into a fuel chamber and an air chamber. The separator wall is deformable according to an amount of fuel in the fuel chamber. The device comprises a device for detecting a change of at least one of a position of the separator wall, the pressure in the tank and the concentration of fuel vapor in the tank, and a device for diagnosing malfunction of the separator wall on the basis of the change to diagnose that the separator wall has malfunction when the change differs from a predetermined regular change.

Abstract: According to the present invention, there is provided a device for diagnosing malfunction in a fuel tank. The fuel tank has a separator wall therein which separates an interior of the fuel tank into a fuel chamber and an air chamber. The separator wall is deformable according to an amount of fuel in the fuel chamber. The device comprises a device for detecting a change of at least one of a position of the separator wall, the pressure in the tank and the concentration of fuel vapor in the tank, and a device for diagnosing malfunction of the separator wall on the basis of the change to diagnose that the separator wall has malfunction when the change differs from a predetermined regular change.

Abstract: A lower wall (8) forming a fuel storage chamber (5) becomes curved downward according to increase of the fuel amount, and at this time a support member (23) for supporting the fuel storage chamber (5) does not restrain the downward curvature of the lower wall (8), whereby the capacity of the fuel storage chamber (5) can be increased and whereby the amount of the fuel that can be stored in the fuel storage chamber (5) can be maintained at the maximum, as compared with structure inhibiting deformation of the lower wall (8).

Abstract: An exhaust gas purifying apparatus of a lean-burn internal combustion engine surely purifies nitrogen oxide occluded by a nitrogen oxide occluding/reducing catalyst without making a combustion of an air-fuel mixture unstable while utilizing a vapor fuel generated in a fuel tank. The exhaust gas purifying apparatus includes a gas state judging unit for judging a state of a vapor fuel gas supplied to an intake system of the lean-burn internal combustion engine, and an exhaust state control unit for setting, to a desired state, a state of the exhaust gas flowing to the nitrogen oxide occluding/reducing catalyst by selectively controlling the fuel injection valve and the gas supply unit in accordance with a state of the vapor fuel gas at the time when the nitrogen oxide occluded by the nitrogen oxide occluding/reducing catalyst provided in an exhaust system of the lean-burn internal combustion engine should be desorbed and purified.

Abstract: A diagnostic apparatus for a fuel vapor treating apparatus closes a breather to shut a purge system valve during purge. While further continuing the purge, the apparatus detects the purge flow thereby caused and a pressure change occurring in the purge system. Based on the purge flow and the pressure change, the space volume in the purge system is estimated. By comparing the estimated space volume and the actual space volume in the purge system, the apparatus determines whether there is a failure or fault in the purge system.

Abstract: A fuel vapor concentration detecting apparatus in a lean-burn internal combustion engine detects a fuel vapor concentration and executes purge control. The apparatus includes an output fluctuation detecting module for detecting, on such an occasion that the fuel vapor is purged into an intake system of the internal combustion engine, an output fluctuation just when the fuel vapor is purged, and a concentration detecting module for calculating the fuel vapor concentration in accordance with a magnitude of the output fluctuation detected by the output fluctuation detecting module. The fuel vapor concentration in the lean-burn internal combustion engine is thus detected. A purge quantity or a state of the fuel injection is changed corresponding to the detected concentration of the fuel vapor.

Abstract: A canister for treating fuel vapor generated in a fuel tank and for supplying fuel vapor to an intake system of an engine via a purge passage. First and second adsorbent compartments are defined in a casing by a partition for accommodating adsorbents. First and second dispersion compartments are defined in the casing for dispersing fuel vapor from the fuel tank. The first and the second dispersion compartments are located at one end of the first and second adsorbent compartments, respectively. A valve device is positioned at one side of the second adsorbent compartment for selectively opening and closing in accordance with the difference between internal and external pressures of the casing. A tank valve is connected to one side of the casing corresponding to the first adsorbent compartment for adjusting the pressure in the fuel tank. An external dispersion compartment is connected to a wall of the casing to communicate with the first dispersion compartment.

Abstract: A fuel vapor feed controlling apparatus of a lean burn internal combustion engine suppresses either one of a rich misfire or a surge when fuel vapor is fed into the engine. A purge controlling unit controls an amount of fuel vapor fed from a fuel reservoir to the engine in response to an operational condition of the engine. A first compensation unit compensates the amount of fuel vapor such that an engine revolution speed of the engine may be identical with a target revolution speed. The purge controlling unit performs a purge control based on a compensation value compensated by the first compensation unit.

Abstract: According to the present invention, there is provided a fuel reserving device for reserving fuel therein comprising a wall for dividing an interior of the device to a fuel chamber and an air chamber, the wall being deformable according to the amount of the fuel in the fuel chamber, a discharge passage which is open to a space formed above the surface of the fuel in the fuel chamber and a shut off valve for normally shutting the discharge passage off. Gas is discharged from the space via the discharge passage when the shut off valve is open. The shut off valve is opened and the gas is discharged from the space when the amount of the gas is larger than a predetermined amount. On the other hand, the shut off valve is closed and the discharging operation of the gas is stopped when the amount of the gas is smaller than the predetermined amount.

Abstract: According to the present invention, there is provided a device for diagnosing malfunction in a fuel tank. The fuel tank has a separator wall therein which separates an interior of the fuel tank into a fuel chamber and an air chamber. The separator wall is deformable according to an amount of fuel in the fuel chamber. The device comprises a device for detecting a change of at least one of a position of the separator wall, the pressure in the tank and the concentration of fuel vapor in the tank, and a device for diagnosing malfunction of the separator wall on the basis of the change to diagnose that the separator wall has malfunction when the change differs from a predetermined regular change.

Abstract: In a remaining fuel amount measuring apparatus for a fuel tank which is suited to the fuel tank designed to suppress generation of fuel vapor, a CPU actuates a piston to supply a prescribed amount of air into a pressure adjusting chamber, thereby increasing the pressure within the pressure adjusting chamber. From the Boyle's law, the increasing rate of air before air supply is inversely proportional to the volume V of the pressure adjusting chamber. Therefore, the CPU, referring to the pressure within the pressure adjusting chamber before and after the air supply, acquires the volume V of the pressure adjusting chamber, and subtracts the volume V of the pressure adjusting chamber from the internal volume of a tank body to acquire the volume of a fuel chamber, i.e. remaining fuel amount.