Abstract: A vane pump including a housing having a peripheral wall portion, a bottom wall portion, and a pump chamber; a rotor disposed in the pump chamber to be rotatable; a vane disposed to be slidable in the radial direction with respect to the rotor and partitioning the pump chamber into working chambers; and a reed valve that opens and closes a discharge hole of the bottom wall portion. A pressure relief groove is disposed in a portion of the bottom wall portion corresponding to the discharge section with a clearance secured between the peripheral wall portion and the pressure relief groove. When the vane overlaps the pressure relief groove, a pair of the working chambers on both sides of the vane in the rotational direction communicates with each other via the pressure relief groove.

Abstract: A vane pump includes a housing, a rotor, a vane and a reed valve. A position at which the sliding direction of the vane with respect to the rotor is inverted from outward to inward is defined as a reference position, and a section of the pump chamber on the discharge hole side with respect to the reference position is defined as a discharge section. A pressure relief groove is disposed in a portion of the bottom wall portion corresponding to the discharge section with a clearance secured between the peripheral wall portion and the pressure relief groove. When the vane overlaps the pressure relief groove, a pair of the working chambers communicate with each other via the pressure relief groove.

Abstract: A vane pump including a housing having a peripheral wall portion, a bottom wall portion, and a pump chamber; a rotor disposed in the pump chamber to be rotatable; a vane disposed to be slidable in the radial direction with respect to the rotor and partitioning the pump chamber into working chambers; and a reed valve that opens and closes a discharge hole of the bottom wall portion. A pressure relief groove is disposed in a portion of the bottom wall portion corresponding to the discharge section with a clearance secured between the peripheral wall portion and the pressure relief groove. When the vane overlaps the pressure relief groove, a pair of the working chambers on both sides of the vane in the rotational direction communicates with each other via the pressure relief groove.

Abstract: A vane pump in which noise can be suppressed is provided. A vane pump (1) includes: a housing (2) having a peripheral wall portion (200), a bottom wall portion (201), and a pump chamber (A); a rotor (3) disposed in the pump chamber (A) to be rotatable; a vane (4) disposed to be slidable in the radial direction with respect to the rotor (3) and partitioning the pump chamber (A) into working chambers (A1, A2); and a reed valve (5) that opens and closes a discharge hole (201a) of the bottom wall portion (201). A position at which the sliding direction of the vane (4) with respect to the rotor (3) is inverted from outward in the radial direction to inward is defined as a reference position (?1), and a section of the pump chamber (A) on the discharge hole (201a) side with respect to the reference position (?1) is defined as a discharge section (AD).

Abstract: An internal combustion engine control apparatus includes a secondary air supply device having a secondary air supply passage that supplies secondary air pumped by an air pump into an exhaust system of an internal combustion engine and an opening/closing unit that opens and closes the secondary air supply passage. A controller provided in the internal combustion engine control apparatus sets the opening/closing unit in an open condition such that the secondary air is supplied to the secondary air supply passage, and then executes foreign matter removal control in which the opening/closing unit is opened and closed. As a result, foreign matter caught in an ASV during AI control is removed immediately. By implementing OBD after removing the foreign matter, detection of an open sticking abnormality caused by foreign matter caught in the ASV is suppressed.

Abstract: A fuel vapor processing apparatus may include a case defining therein a first adsorption chamber, a second adsorption chamber and a non-adsorption chamber communicating between the first adsorption chamber and the second adsorption chamber. The cross sectional flow area of the first adsorption chamber may be smaller than the cross sectional flow area of the second adsorption chamber.

Abstract: An internal combustion engine control apparatus includes a secondary air supply device having a secondary air supply passage that supplies secondary air pumped by an air pump into an exhaust system of an internal combustion engine and an opening/closing unit that opens and closes the secondary air supply passage. A controller provided in the internal combustion engine control apparatus sets the opening/closing unit in an open condition such that the secondary air is supplied to the secondary air supply passage, and then executes foreign matter removal control in which the opening/closing unit is opened and closed. As a result, foreign matter caught in an ASV during AI control is removed immediately. By implementing OBD after removing the foreign matter, detection of an open sticking abnormality caused by foreign matter caught in the ASV is suppressed.

Abstract: A fuel vapor processing apparatus may include a case defining therein a first adsorption chamber, a second adsorption chamber and a non-adsorption chamber communicating between the first adsorption chamber and the second adsorption chamber. The cross sectional flow area of the first adsorption chamber may be smaller than the cross sectional flow area of the second adsorption chamber.

Abstract: A fuel vapor processing apparatus includes a case defining therein a flow passage including an adsorption chamber, an adsorption material disposed in the adsorption chamber; and a density gradient filter disposed in the flow passage at a position on an upstream side of the adsorption material with respect to a direction of flow of purge air for desorbing fuel vapor from the adsorption material. The density gradient filter includes a first portion having a first density, a second portion having a second density, and a third portion having a third density. The third portion is positioned on a downstream side of the first portion with respect to the direction of flow of the purge air and the second portion is positioned between the first portion and the third portion. Each of the first density and the third density is higher than the second density.

Abstract: A purge valve and an atmosphere opening valve are closed at a timing for stopping purge, so that a canister is sealed from an atmosphere. Thus, even when purge is stopped, the interior of the canister can be held in a negative pressure state. Therefore, adsorbed fuel does not return to inner depths of pores of an adsorbent, thus maintaining a state where the fuel is present on a surface side of the adsorbent. Thus, when purge is resumed, fuel vapors are swiftly discharged to an intake passage of an internal combustion engine via a purge passage. Thereafter as well, fuel vapors continue to be discharged due to the fuel rising to the surface from the inner depths of the pores of the adsorbent. When purge is thus resumed, fuel vapors are immediately discharged from the canister with no time lag.

Abstract: An evaporative fuel treatment system is disclosed that includes a canister, a detection passage having a reduced area portion, and switching device that switches fluid communication. Also included is a depressurizing device for depressurizing the detection passage coupled to the detection passage on a side of the reduced area portion opposite to the switching device, and a pressure detecting device. Moreover, the system includes an evaporative fuel state calculating device for calculating an evaporative fuel state in the mixture based on a cutoff pressure, an air pressure, and a mixture pressure of a mixture of air and the evaporative fuel. In one embodiment, the cutoff pressure, the air pressure, and the mixture pressure are detected independently and discontinuously. In another embodiment, the cutoff pressure and the air pressure are detected on a continual basis during purge of the evaporative fuel.

Abstract: A concentration-detecting unit detects concentration of fuel vapor flowing in a concentration-detecting passage branched from a purge passage. The concentration-detecting passage communicates with a communicating passage of a canister. Air including the fuel vapor of which concentration is detected by a concentration-detecting unit is returned to the communicating passage of the canister. The fuel vapor is adsorbed by an absorbent accommodated in a accommodating chamber to restrict a discharge of the fuel vapor into atmosphere.

Abstract: A fuel vapor treatment apparatus includes a first canister, a purge passage, an atmosphere passage, a first detection passage provided with a restrictor, and a passage-changing valve for changing the connection passage of the first detection passage between the purge passage and the atmosphere passage. The apparatus further includes a second canister connecting with the first detection passage on the opposite side of the passage-changing valve across the restrictor. A differential pressure sensor detects a pressure difference between both ends of the restrictor. An ECU computes the concentration of fuel vapor on the basis of the detection result of the differential pressure sensor.

Abstract: When a gas flow producer is driven, plural kinds of gases flow into a measure-passage at respective timing. An orifice is provided in the measure-passage. The orifice has a diameter-changing portion which restricts a separation of gases from an inner surface of the measure-passage. A pressure sensor is provided in the measure-passage to detect a pressure determined by the orifice and the gas flow producer. A microcomputer calculates a density ratio between the gases based on the detected differential pressure.

Abstract: When a gas flow producer is driven, plural kinds of gases flow into a measure-passage at respective timing. An orifice is provided in the measure-passage. The orifice has a diameter-changing portion which restricts a separation of gases from an inner surface of the measure-passage. A pressure sensor is provided in the measure-passage to detect a pressure determined by the orifice and the gas flow producer. A microcomputer calculates a density ratio between the gases based on the detected differential pressure.

Abstract: An evaporative fuel treatment system is disclosed that includes a canister, a detection passage having a reduced area portion, and switching device that switches fluid communication. Also included is a depressurizing device for depressurizing the detection passage coupled to the detection passage on a side of the reduced area portion opposite to the switching device, and a pressure detecting device. Moreover, the system includes an evaporative fuel state calculating device for calculating an evaporative fuel state in the mixture based on a cutoff pressure, an air pressure, and a mixture pressure of a mixture of air and the evaporative fuel. In one embodiment, the cutoff pressure, the air pressure, and the mixture pressure are detected independently and discontinuously. In another embodiment, the cutoff pressure and the air pressure are detected on a continual basis during purge of the evaporative fuel.

Abstract: A concentration-detecting unit detects concentration of fuel vapor flowing in a concentration-detecting passage branched from a purge passage. The concentration-detecting passage communicates with a communicating passage of a canister. Air including the fuel vapor of which concentration is detected by a concentration-detecting unit is returned to the communicating passage of the canister. The fuel vapor is adsorbed by an absorbent accommodated in a accommodating chamber to restrict a discharge of the fuel vapor into atmosphere.

Abstract: A fuel vapor treatment apparatus includes a first canister, a purge passage, an atmosphere passage, a first detection passage provided with a restrictor, and a passage-changing valve for changing the connection passage of the first detection passage between the purge passage and the atmosphere passage. The apparatus further includes a second canister connecting with the first detection passage on the opposite side of the passage-changing valve across the restrictor. A differential pressure sensor detects a pressure difference between both ends of the restrictor. An ECU computes the concentration of fuel vapor on the basis of the detection result of the differential pressure sensor.

Abstract: An adsorbent for adsorbing fuel vapors is disclosed. The adsorbent is to be disposed in an inlet system of an internal combustion engine. It has pores, and 50% by volume or more of the pores have a pore diameter falling in a range of from 1.4 to 2.8 nm. It exhibits a unit pore volume of 0.3 mL or more with respect to 1 mL thereof. It is formed as a particle. It exhibits high performance on adsorbing fuel vapors, and shows high durability even when it is used for long period of time.

Abstract: An adsorbent for adsorbing fuel vapors is disclosed. The adsorbent is to be disposed in an inlet system of an internal combustion engine. It has pores, and 50% by volume or more of the pores have a pore diameter falling in a range of from 1.4 to 2.8 nm. It exhibits a unit pore volume of 0.3 mL or more with respect to 1 mL thereof. It is formed as a particle. It exhibits high performance on adsorbing fuel vapors, and shows high durability even when it is used for long period of time.