Abstract: An intake device for an internal combustion engine has: a first intake pipe which is connected to the engine so as to conduct an intake air to the engine, and which has an opening portion that is provided in an upstream-side lower portion of the first intake pipe located at an upstream side in a flowing direction of the intake air; and a second intake pipe which has a downstream-side end portion that faces an upstream-side end portion of the first intake pipe, with a gap formed therebetween, and which conducts the intake air to the first intake pipe. An unburned gas reflux passage is provided for conducting an unburned gas from the engine to the first intake pipe. A container surrounds the gap and the opening so as to receive the unburned gas flowing from the opening portion. Thus, it becomes possible to prevent release of unburned gas into the atmosphere by performing a simple process on a conventional structure.

Abstract: An HC adsorbing sheet inside an air cleaner is disposed such that a large amount of activated carbon is contained on the side of an engine and that a small amount of activated carbon is contained on the other side of the engine. Thus, the HC adsorbing sheet can efficiently adsorb evaporative fuel. That is, by changing the amount of activated carbon contained in accordance with differences in concentration of evaporative fuel, it becomes possible to prevent the pressure loss in an intake system from increasing. On the other hand, one end of a second intake pipe extends to a region where the amount of activated carbon contained in the HC adsorbing sheet is large, whereby it becomes possible to concentratively supply activated carbon with intake air in the region where the large amount of activated carbon is contained. Therefore, the efficiency in purging evaporative fuel can be prevented from declining.

Abstract: An absorbent, such as, for example, an active carbon, is provided in an intake air passage, for example, in an air cleaner, to efficiently adsorb fuel vapor. To ensure that fuel vapor adsorbed into the intake air passage can be efficiently desorbed even when there is only a small amount of the intake air, an intake throttle valve is provided upstream of the adsorbent and an opening of the intake throttle valve is throttled so as to decompress an area near the adsorbent. Desorption of fuel vapor also can be efficiently promoted by using a heater to directly heat the adsorbent in the intake air passage or by heating the intake air to indirectly heat the adsorbent.

Abstract: A fuel vapor handling apparatus supplies a purging air to a canister by using a purge pump and purges fuel desorbed from the canister into an intake pipe. A controller intermittently operates the purge so that the canister internal temperature recovers from a reduced level caused by the latent heat of vaporization of fuel during an operating period of the purge pump. Therefore, desorption of fuel from the canister during an operating period is facilitated. Since the actual operating time of the purge pump is reduced, the life of a motor that is a power unit of the purge pump becomes longer.

Abstract: An intake device for an internal combustion engine has: a first intake pipe which is connected to the engine so as to conduct an intake air to the engine, and which has an opening portion that is provided in an upstream-side lower portion of the first intake pipe located at an upstream side in a flowing direction of the intake air; and a second intake pipe which has a downstream-side end portion that faces an upstream-side end portion of the first intake pipe, with a gap formed therebetween, and which conducts the intake air to the first intake pipe. An unburned gas reflux passage is provided for conducting an unburned gas from the engine to the first intake pipe. A container surrounds the gap and the opening so as to receive the unburned gas flowing from the opening portion. Thus, it becomes possible to prevent release of unburned gas into the atmosphere by performing a simple process on a conventional structure.

Abstract: A sheet-like adsorption filter formed by sandwiching particulate activated carbon with heat-resistant nets and non-woven fabric sheets that have a percentage of void of 90% or higher, is disposed at an internal combustion engine side of a filter element.

Abstract: A fuel adsorption layer formed in a canister is partitioned into an upper adsorption layer and a lower adsorption layer by a partition plate in which a heater is embedded. The relation between a heating value of the heater and thickness X of the upper and lower adsorption layers is set so that the temperature of a part closest to the heater heating face of the fuel adsorption layer is lower than a fire point of the fuel, and the temperature of a part farthest from the heater heating face is higher than the boiling point of the fuel. With the configuration, by heating the fuel adsorption layer by the heater, the desorption performance of activated carbon is improved, and almost all of the fuel vapors adsorbed can be desorbed.

Abstract: A shut valve is provided in an intake line farther upstream than a throttle valve of the intake line and farther downstream than an air cleaner. This shut valve is opened by a signal or the like from an ECU when an engine is operating. Further, the shut valve closes when the engine is stopped so as to suppress evaporative fuel inside the intake line from flowing outside through the air cleaner. The evaporative fuel trapped inside the intake line passes through a bypass passage that provides communication between the intake line and the canister, and is then adsorbed with an adsorbent in the canister. A blow-by line is also connected to the intake line that is closed off by the shut valve. Because the blow-by line is closed off by a blow-by valve, which is closed during normal operation, when the engine is stopped, sticking of the shut valve and the throttle valve and the like due to the inflow of blow-by gas into the intake line is inhibited.

Abstract: An HC adsorbing sheet inside an air cleaner is disposed such that a large amount of activated carbon is contained on the side of an engine and that a small amount of activated carbon is contained on the other side of the engine. Thus, the HC adsorbing sheet can efficiently adsorb evaporative fuel. That is, by changing the amount of activated carbon contained in accordance with differences in concentration of evaporative fuel, it becomes possible to prevent the pressure loss in an intake system from increasing. On the other hand, one end of a second intake pipe extends to a region where the amount of activated carbon contained in the HC adsorbing sheet is large, whereby it becomes possible to concentratively supply activated carbon with intake air in the region where the large amount of activated carbon is contained. Therefore, the efficiency in purging evaporative fuel can be prevented from declining.

Abstract: An absorbent, such as, for example, an active carbon, is provided in an intake air passage, for example, in an air cleaner, to efficiently adsorb fuel vapor. To ensure that fuel vapor adsorbed into the intake air passage can be efficiently desorbed even when there is only a small amount of the intake air, an intake throttle valve is provided upstream of the adsorbent and an opening of the intake throttle valve is throttled so as to decompress an area near the adsorbent. Desorption of fuel vapor also can be efficiently promoted by using a heater to directly heat the adsorbent in the intake air passage or by heating the intake air to indirectly heat the adsorbent.

Abstract: A throttle valve is opened after stopping an engine to prevent the valve from sticking. Then, when a temperature of the valve has become lower than the polymerization temperature, the valve is closed to seal the vapor of the HCs in a surge tank downstream. Changes in the temperature of the valve are, for example, estimated based on a temperature of an intake air detected by an intake temperature sensor.

Abstract: A fuel vapor handling apparatus supplies a purging air to a canister by using a purge pump and purges fuel desorbed from the canister into an intake pipe. A controller intermittently operates the purge so that the canister internal temperature recovers from a reduced level caused by the latent heat of vaporization of fuel during an operating period of the purge pump. Therefore, desorption of fuel from the canister during an operating period is facilitated. Since the actual operating time of the purge pump is reduced, the life of a motor that is a power unit of the purge pump becomes longer.

Abstract: A fuel adsorption layer formed in a canister is partitioned into an upper adsorption layer and a lower adsorption layer by a partition plate in which a heater is embedded. The relation between a heating value of the heater and thickness X of the upper and lower adsorption layers is set so that the temperature of a part closest to the heater heating face of the fuel adsorption layer is lower than a fire point of the fuel, and the temperature of a part farthest from the heater heating face is higher than the boiling point of the fuel. With the configuration, by heating the fuel adsorption layer by the heater, the desorption performance of activated carbon is improved, and almost all of the fuel vapors adsorbed can be desorbed. As a result, the fuel vapors do not remain in the canister, so that all of the fuel vapors which flow in at the time of adsorption can be adsorbed with reliability.

Abstract: A sheet-like adsorption filter formed by sandwiching particulate activated carbon with heat-resistant nets and non-woven fabric sheets that have a percentage of void of 90% or higher, is disposed at an internal combustion engine side of a filter element.

Abstract: A damping chamber is formed in a pressure relaxation device connected to a high pressure fuel pipe. Valve bodies are provided at openings of partitions, and a spring force is applied to the valve bodies by a spring in a valve closing direction. When a high pressure portion reaches an inlet of the damping chamber, the valve body opens to hold and absorb the high pressure portion in the damping chamber. When a low pressure portion reaches the inlet of the damping chamber, the high pressure portion held in the damping chamber is gradually released via a restricted orifice to cancel the low pressure portion, thereby reducing the pressure pulsation of fuel.

Abstract: To excellently grow flame kernel while lowering breakdown voltage, a bypass electrode comprising a semiconductor material is installed in a path bypassing an inductive spark gap between a center electrode and a ground electrode, and the center electrode and the ground electrode are electrically connected by the bypass electrode and capacitive discharge is carried out by applying breakdown voltage between the center electrode and the ground electrode via the bypass electrode, and thereafter, inductive discharge is carried out through the inductive spark gap.

Abstract: A gas ventilation system for an internal combustion engine is provided which includes a downstream intake pipe communicating with cylinders of the engine, an upstream intake pipe communicating with the downstream intake pipe through a throttle valve, and a gas ventilation pipe for recirculating a given gas to the engine. The system also has an inner hollow cylinder connected to the upstream intake pipe, disposed within the downstream intake pipe to define a gas passage between the periphery of the inner cylinder and an inner wall of the downstream intake pipe. The gas passage communicates with the gas ventilation pipe and serves as an isolating member for isolating flow of the gas entering the downstream intake pipe through the gas ventilation pipe from swirls produced by intake air flowing downstream of the throttle valve from the upstream intake pipe.

Abstract: A gas/liquid separator device includes a separator, such as a cyclone type separator, provided in a blowby gas passage for introducing a blowby gas from a blowby gas chamber of an internal combustion engine, an oil accumulator in the form of a container for accumulating separated and condensed oil mist, another passage provided separately from the blowby gas passage for returning the oil from the oil accumulator to an oil collection chamber, and a communication blocking element for blocking a communication between the oil accumulator and the oil collection chamber while the engine is running.