Abstract: A fuel vapor processing apparatus includes an adsorbent canister, a vapor path connecting the adsorbent canister to a fuel tank, and a flow control valve disposed in the vapor path. The flow control valve is kept closed while a movement distance of a valve body from a predetermined initial position toward a valve opening direction is less than a predetermined distance. A control unit comprising part of the apparatus is configured to set a valve opening speed of the flow control valve to a first speed under a condition where the movement distance of the valve body is less than the predetermined distance, and to set the valve opening speed of the flow control valve to a second speed lower than the first speed under a condition where the movement distance of the valve body is greater than the predetermined distance.

Abstract: A fuel vapor processing apparatus may include a canister capable of adsorbing fuel vapor produced in a fuel tank, a closing valve provided in a vapor passage connecting the canister and the fuel tank, a purge passage connecting the canister and an intake passage of an engine, and a control device. The closing valve may include a movable valve member movable along a linear path and an actuator coupled to the movable valve member. The control device may be coupled to the actuator and may be configured to control the actuator such that the position of the movable valve member along the linear path changes according to a deviation of an actual tank internal pressure of the fuel tank from a target tank internal pressure.

Abstract: An evaporated fuel treatment device includes a canister, an evaporated fuel outflow detecting means, a pressure sensor, a pressure change detecting means, and a pressure sensor failure determining means. The canister adsorbs evaporated fuel from a fuel tank, and purges the adsorbed fuel to an engine. The evaporated fuel outflow detecting means undergoes a change in a signal as the evaporated fuel flows out of the fuel tank. The pressure sensor detects an inner pressure of the fuel tank. The pressure change detecting means detects whether or not the pressure is in a static state. When the evaporated fuel outflow detecting means detects that evaporated fuel has flowed out of the fuel tank and when the pressure change detecting means detects that the pressure is in a static state, the pressure sensor failure determining means determines that the pressure sensor is out of order.

Abstract: An evaporated fuel processing device has a canister, a vapor passage, a purge passage, a shutoff valve, a storage device and a control device. The canister includes an adsorbent material that adsorbs evaporated fuel generated in a fuel tank. The vapor passage connects the canister and the fuel tank. The purge passage connects the canister and an intake passage of an engine. The shutoff valve is provided in the vapor passage, and adjusts flow rate of gas flowing through the vapor passage. The storage device stores in advance a reference value for the shutoff valve corresponding to internal pressure of the fuel tank. The shutoff valve is controlled based on the reference value, which is obtained from the internal pressure of the fuel tank, and pressure release control is performed on the fuel tank.

Abstract: A fuel vapor processing apparatus includes a vapor path connecting an adsorbent canister to a tank, where a valve is disposed in the vapor path and comprises a body and a seat, and a control unit configured to detect a movement distance of the body from the seat as a valve movement distance at a valve opening start position. This position results when a change in inner pressure of the tank after starting movement of the body toward a valve opening direction becomes greater in magnitude than a predetermined amount, wherein the control unit stores the valve movement distance in the valve opening direction as a learning value, and also stores one of two predetermined restriction values as the learning value instead of the valve movement distance when the valve movement distance is not within a range between a previously stored learning value and one of the restriction values.

Abstract: A fuel-supply system has a fuel pump, a pressure controller, a signal output device and a power switch. The pressure controller adjusts the observed fuel pressure of the fuel and may electronically communicate with a motor driving the fuel pump to regulate the supply of fuel from a fuel tank of the fuel-supply system to an engine. In detail, the pressure controller performs feedback control of a voltage applied to the motor such that the pressure of a fuel pumped from the fuel pump approaches to have a first target and/or ideal fuel pressure value. Further, the signal output device outputs the first target fuel pressure value to the pressure controller. Activation of the power switch supplies power, from a power source, to the pressure controller, the motor and the signal output device. Further, the pressure controller may perform feedback control based on a second target fuel pressure value.

Abstract: A vaporized fuel treating device having a canister that is configured to adsorb vaporized fuel in a fuel tank and to feed the adsorbed vaporized fuel to an engine may include a pressure sensor that is configured to periodically detect an inner pressure of the fuel tank, and a pressure sensor failure determination device that is configured to determine that the pressure sensor has failed when a change of the inner pressure detected by the pressure sensor in a unit of time is not less than a predetermined pressure value that is greater than a maximum value of possible pressure changes within the fuel tank.

Abstract: A fuel vapor processing apparatus includes a canister housing an adsorbent material that adsorbs fuel vapor from a tank, and a valve in a passage connecting the canister and tank. When a stroke amount is within a range, the valve is closed to close the tank and a valve opening start position is learned. In the learning, the stroke amount is varied in the opening direction by repeatedly changing in the opening direction by a first stroke and maintaining for a first time period, and subsequently changing in a closing direction by a second stroke and maintaining for a second time period. The valve opening start position is determined based on the stroke amount in the second time period when the tank pressure is reduced by the predetermined value or more or in a preceding process.

Abstract: A vaporized fuel processing apparatus has a canister capable of adsorbing vaporized fuel generated in a fuel tank, a vapor path connecting the canister to the fuel tank, a closing valve provided in the vapor path, a purge path connecting the canister to an intake path of an engine, a pressure sensor for detecting the inner pressure of the fuel tank, and an electric control unit controlling the vaporized fuel processing apparatus. When the inner pressure of the fuel tank is in excess of the measurement range of the pressure sensor, the learning of the valve opening start position is prohibited, and pre-learning depressurization control is performed through change of the stroke amount of the closing valve in the valve opening direction until the inner pressure of the fuel tank is within the measurement range of the pressure sensor.

Abstract: A vaporized fuel processing apparatus has a closing valve provided in a vapor path connecting an adsorbent canister to the fuel tank, a pressure sensor configured to detect the inner pressure of the fuel tank, and an electric control unit configured to determine whether the amount of increase in the inner pressure of the fuel tank is within an acceptable range or not, to learn a valve opening start position of the closing valve when the inner pressure of the fuel tank is reduced by an amount not less than a predetermined value, and to stop or prohibit the learning of the valve opening start position of the closing valve when the amount of increase in the inner pressure of the fuel tank is not within the acceptable range during or before the learning of the valve opening start position of the closing valve.

Abstract: A fuel vapor processing apparatus includes an adsorbent canister, a vapor path connecting the adsorbent canister to a fuel tank, and a flow control valve disposed in the vapor path. The flow control valve is kept closed while a movement distance of a valve body from a predetermined initial position toward a valve opening direction is less than a predetermined distance. A control unit comprising part of the apparatus is configured to set a valve opening speed of the flow control valve to a first speed under a condition where the movement distance of the valve body is less than the predetermined distance, and to set the valve opening speed of the flow control valve to a second speed lower than the first speed under a condition where the movement distance of the valve body is greater than the predetermined distance.

Abstract: An evaporated fuel treatment device includes a canister, an evaporated fuel outflow detecting means, a pressure sensor, a pressure change detecting means, and a pressure sensor failure determining means. The canister adsorbs evaporated fuel from a fuel tank, and purges the adsorbed fuel to an engine. The evaporated fuel outflow detecting means undergoes a change in a signal as the evaporated fuel flows out of the fuel tank. The pressure sensor detects an inner pressure of the fuel tank. The pressure change detecting means detects whether or not the pressure is in a static state. When the evaporated fuel outflow detecting means detects that evaporated fuel has flowed out of the fuel tank and when the pressure change detecting means detects that the pressure is in a static state, the pressure sensor failure determining means determines that the pressure sensor is out of order.

Abstract: A fuel vapor processing apparatus includes a vapor path connecting an adsorbent canister to a tank, where a valve is disposed in the vapor path and comprises a body and a seat, and a control unit configured to detect a movement distance of the body from the seat as a valve movement distance at a valve opening start position. This position results when a change in inner pressure of the tank after starting movement of the body toward a valve opening direction becomes greater in magnitude than a predetermined amount, wherein the control unit stores the valve movement distance in the valve opening direction as a learning value, and also stores one of two predetermined restriction values as the learning value instead of the valve movement distance when the valve movement distance is not within a range between a previously stored learning value and one of the restriction values.

Abstract: A vaporized fuel processing apparatus has a fuel tank, a canister configured to adsorb vaporized fuel, a vapor path connecting the canister to the fuel tank, a closing valve provided in the vapor path, a pressure sensor measuring inner pressure of the fuel tank, and an electric control unit connected with the closing valve and the pressure sensor. The electric control unit is configured to close or open the closing valve in order to initialize the closing valve or open the closing valve in order to release the vaporized fuel from the fuel tank. Further, the electric control unit is configured to detect failure of the closing valve depending on change in the inner pressure of the fuel tank within a predetermined time from when the closing valve is opened or is closed for initialization of the closing valve or release of the vaporized fuel from the fuel tank.

Abstract: A fuel supply system may include a fuel pump configured to supply fuel from a fuel tank to a target, a motor for driving the fuel pump, and a controller coupled to the motor. The controller may determine a duty ratio of a control signal through a feedback control and to output the control signal to the motor, so that a fuel pressure of the fuel supplied from the fuel tank approaches a target fuel pressure. The controller may estimate the duty ratio based on the target fuel pressure and information regarding a fuel pressure of the fuel supplied from the fuel tank, and may guard an upper limit of the duty ratio by an upper limit guard value. The upper limit guard value may be determined based on a rotational speed of the motor.

Abstract: A fuel supply system for an internal combustion engine has a fuel pump capable of pumping fuel from a fuel tank to the internal combustion engine, a motor driving the fuel pump, a pressure sensor configured to detect pressure of the fuel pumped from the fuel pump, and a control unit configured to output control signals to the motor. The control unit is configured to perform feedback control of duty ratio of the control signals for the motor, and to control the duty lower limit guard value in order to limit an amount of decreases of the duty lower limit guard value in the step-like manner when a duty lower limit guard value decreases.

Abstract: A vaporized fuel processing apparatus has a closing valve provided in a vapor path connecting an adsorbent canister to the fuel tank, a pressure sensor configured to detect the inner pressure of the fuel tank, and an electric control unit configured to determine whether the amount of increase in the inner pressure of the fuel tank is within an acceptable range or not, to learn a valve opening start position of the closing valve when the inner pressure of the fuel tank is reduced by an amount not less than a predetermined value, and to stop or prohibit the learning of the valve opening start position of the closing valve when the amount of increase in the inner pressure of the fuel tank is not within the acceptable range during or before the learning of the valve opening start position of the closing valve.

Abstract: A vaporized fuel processing apparatus has a canister capable of adsorbing vaporized fuel generated in a fuel tank, a closing valve provided in the vapor path connecting the canister and the fuel tank and having a valve seat and a valve movable portion, a pressure sensor configured to detect inner pressure of the fuel tank, and an electric control unit. The electric control unit is configured to set a learning value that is an axial distance between the valve seat and the valve movable portion at a valve opening start position at a fail-safe value such that the closing valve is in the valve closing state when the inner pressure of the fuel tank decreases by less than a predetermined value after repeating a stroke control process more than predetermined times.

Abstract: A fuel vapor processing apparatus includes a canister housing an adsorbent material that adsorbs fuel vapor from a tank, and a valve in a passage connecting the canister and tank. When a stroke amount is within a range, the valve is closed to close the tank and a valve opening start position is learned. In the learning, the stroke amount is varied in the opening direction by repeatedly changing in the opening direction by a first stroke and maintaining for a first time period, and subsequently changing in a closing direction by a second stroke and maintaining for a second time period. The valve opening start position is determined based on the stroke amount in the second time period when the tank pressure is reduced by the predetermined value or more or in a preceding process.

Abstract: A vaporized fuel processing apparatus has a canister loaded with an adsorbent capable of adsorbing vaporized fuel generated in a fuel tank, a closing valve provided a vapor path connecting the canister and the fuel tank and having a valve seat and a valve movable portion such that a distance between the valve seat and the valve movable portion is stroke amount, a pressure sensor configured to detect inner pressure of the fuel tank, and an electric control unit. The electric control unit is configured to perform abnormal state depressurization control of the fuel tank, in a state that the pressure sensor cannot detect the inner pressure of the fuel tank, by setting the stroke amount of the closing valve at a fail-safe value in which the closing valve is closed, and then changing the stroke amount in a valve opening direction of the closing valve from the fail-safe value.