Disclosed is a device for evaporating vapors of a fuel stored in a motor vehicle tank. The evaporation device includes a bypass circuit and a bypass valve configured to move between a so-called “absorption” position, in which the bypass valve allows the gases to flow between the tank and an absorbent filter and a so-called “leak detection” position, in which the bypass valve allows the gases to flow between a purge circuit and the tank via the bypass circuit.

A method and device for diagnosing a leak in an evaporation system and in a tank ventilation line of an internal combustion engine is disclosed. The method includes diagnosing the entire evaporation system using a fresh-air shut-off valve of the evaporation system and a pressure sensor system of the evaporation system. During the check on whether there is a leak in the evaporation system of the internal combustion engine, a separate check of different diagnosis regions of the evaporation system is undertaken, where one of these diagnosis regions is a tank region of the internal combustion engine and a further diagnosis region is a filter region of the internal combustion engine. During the diagnosis of the tank ventilation line, the flow through the tank ventilation line is checked.

Provided is a canister that includes a first adsorbing layer K1 including a first adsorbing material Q1 as an adsorbing material Q and a second adsorbing layer K2 including, as the adsorbing material Q, a second adsorbing material Q2 different from the first adsorbing material Q1. The first absorbing layer K1 and the second absorbing layer K2 are provided inside a casing 10. In a flowing direction of fuel vapor J between one end and another end of the casing 10, the first adsorbing layer K1 is disposed at a position in contact with an air port 10a at the other end, and the second adsorbing layer K2 is disposed closer to the one end than the first adsorbing layer K1 is. The first adsorbing material Q1 adsorbs the fuel vapor J at an adsorbing rate that is lower than an adsorbing rate of the second adsorbing material Q2.

Provided is a canister that includes a first adsorbing layer K1 including a first adsorbing material Q1 as an adsorbing material Q and a second adsorbing layer K2 including, as the adsorbing material Q, a second adsorbing material Q2 different from the first adsorbing material Q1. The first absorbing layer K1 and the second absorbing layer K2 are provided inside a casing 10. In a flowing direction X of fuel vapor J between one end and another end of the casing 10, the first adsorbing layer K1 is disposed at a position in contact with an air port 10a at the other end, and the second adsorbing layer K2 is disposed closer to the one end than the first adsorbing layer K1 is. The first adsorbing material Q1 adsorbs the fuel vapor J at an adsorbing rate that is higher than an adsorbing rate of the second adsorbing material Q2.

Provided is a canister including at least one chamber, an inflow port, an atmosphere port, an outflow port, and a plurality of rod-shaped portions. In the at least one chamber, an adsorbent for fuel vapor is arranged. The plurality of rod-shaped portions is a plurality of elongated portions arranged in an object chamber, which is any of the at least one chamber. The adsorbent arranged in the object chamber is formed as a plurality of granular bodies. At least a part of the plurality of rod-shaped portions has, on an outer peripheral surface thereof, at least one recess formed.

A fuel system, a vehicle, and a method of controlling an evaporative emissions system for the vehicle are provided. The fuel system has a fuel tank having a fuel fill port with a closure member. An evaporative emissions canister has a first port fluidly coupled to the fuel tank to receive vapor therefrom and a second port, with the canister positioned between an air intake for an engine and a vent to atmosphere. A filter or a second canister is supported by a bracket for movement between first and second positions, with the filter fluidly coupling the second port of the canister to the vent in the first position, and the filter spaced apart from and decoupled from the second port of the canister in the second position. The second port of the canister is in direct fluid communication with atmosphere when the filter is in the second position.

A vehicle canister device includes a main canister including an inlet port through which evaporative gas is introduced from a fuel tank, an outlet port through which the evaporative gas introduced during operation of an engine is discharged to an intake side of the engine, and an internal space for filling activated carbon. The vehicle canister device also includes an auxiliary canister mounted in fluid-communication with the main canister and configured to allow external air to flow into the main canister through an atmosphere port provided on the main canister or the evaporative gas to flow therethrough upon stop of the engine. The auxiliary canister includes a plurality of activated carbon layers each filled with an activated carbon and a plurality of air layers disposed between the activated carbon layers.

A vehicle includes an engine, a fuel tank, a primary canister, a buffer canister, a purge valve, a check valve, and a controller. The fuel tank is configured to store fuel. The primary canister is configured to receive and store evaporated fuel from the fuel tank. The buffer canister is configured to receive and store the evaporated fuel from the fuel tank. The buffer canister is disposed between the primary canister and the engine. The purge valve is disposed between the buffer canister and the engine. The purge valve is configured to direct the evaporated fuel from the primary and buffer canisters to the engine when open. The check valve is disposed between the primary and buffer canisters and is configured to restrict backflow of the evaporated fuel from the buffer canister toward the primary canister. The controller is programmed to diagnose the operability of the check valve.

Methods and systems are provided for regulating evaporative emissions from a fuel system. In one example, a method may comprise spinning an engine unfueled responsive to a hydrocarbon concentration at a fresh air end of a fuel vapor canister increasing above a first threshold. The method may comprise spinning the engine to pull hydrocarbons away until a hydrocarbon concentration at a purge end of the fuel vapor canister, opposite the fresh air end, increases above a second threshold.

An evaporated fuel treatment device is provided with an electric-operated valve, a positive-pressure relief valve mechanism and a negative-pressure relief valve mechanism. The electric-operated valve has a valve body for opening/closing a vapor passage allowing a fuel tank and a canister, and adjusts the flow rate by electrical control. The positive-pressure relief valve mechanism opens when the pressure at the fuel tank side has a value greater than or equal to a predetermined positive pressure value. The negative-pressure relief valve mechanism opens when the pressure at the fuel tank side has a value less than or equal to a predetermined negative pressure value. The electric-operated valve is configured such that the valve body is moved in the valve opening direction by the pressure at the fuel tank side that is higher, by a predetermined value, than the valve opening pressure for the positive-pressure relief valve mechanism.