JPH01300046A - Canister for controlling onboard - Google Patents

Abstract

PURPOSE:To reduce the concentration of vapor gas supplied to an engine so as to stabilize operation conditions of engine by arranging active carbon layer between the intake and release sides of a canister taking vapor gas in a fuel tank in. CONSTITUTION:When gasoline is supplied to a tank 10 from an intake port 11, vapor gas in the tank 10 is introduced in a pipe 4 of a canister 1 through a vapor gas passage 6 from a air valve 12. The canister 1 is provided with a pipe 4 and a check valve 2 at the intake side of vapor gas and pipe 5 and a check valve 3 at the release side. In this case, inside the canister 1, active carbon is arranged. The vapor gas introduced into the pipe 4 is adsorbed by the active carbon layer and only air is discharged from the check valve 3. The vapor gas adsorbed by the layer is led out to a purge passage 7 from the pipe 5 by use of the negative pressure generated at an intake manifold 8 of an engine.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a canister used for controlling evaporative gas during refueling, and particularly when the canister is detached immediately after inhaling evaporative gas.
This invention relates to a canister that does not release excessive evaporated gas.

[Conventional technology]

In the conventional device, the evaporative gas suction side and the desorption side are arranged on the same side, as described in Public Utility Model No. 1984-38470.

[Problem to be solved by the invention]

The above conventional technology does not give sufficient consideration to the fact that a large amount of evaporative gas is released during desorption immediately after inhalation of evaporative gas, and a large amount of evaporative gas is released during desorption and the desorption light is the fuel supplied to the engine. There was a problem with too many.

An object of the present invention is to provide a structure in which excessive evaporative gas is not desorbed by arranging the evaporative gas suction side and the desorption side with an activated carbon layer in between.

[Means to solve the problem]

The above object is achieved by arranging the evaporative gas suction side and the desorption side with an activated carbon layer in between, and configuring one check valve on each of the suction side and the desorption side.

[Effect]

The inhaled evaporated gas is introduced into the suction side space and is gradually adsorbed by the activated carbon layer. Even if it enters a desorption state immediately, it is sucked in with negative pressure from the desorption side with the activated carbon layer in between, so the evaporated gas floating in the suction side space always passes through the activated carbon layer and is adsorbed until it reaches the desorption side. can be absorbed and desorbed at a reduced concentration. This prevents excess fuel from being supplied to the engine, stabilizes the engine speed, and prevents the generation of substances harmful to the human body in the exhaust gas.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

In this embodiment, the gasoline inlet 11 is connected to the gasoline tank 1.
When refueling with gasoline, the evaporative gas accumulated in the gasoline tank 10 is guided to the pipe 4 of the canister 1 through the evaporative gas passage 6 by opening the air valve 12. As shown in FIG. 2, the canister 1 has a pipe 4 on the evaporative gas suction side, a check valve 2, and a pipe 5 on the desorption side. A check valve 3 is provided, and a case 1 and a cover 20 form a container.

In this, perforated plates 13, 18. Filters 14 and 17 are placed and activated carbon 15 is pressed down and held by springs 19. Since the check valve 3 is open to the atmosphere, the evaporated gas led to the pipe 4 passes through the 15 layers of activated carbon from the pipe 4 and is released from the check valve 3 to the atmosphere. Evaporated gas is activated carbon 1
5 layers, and only air is released from the check valve 3 to the atmosphere. This can prevent evaporative gas generated during refueling from dissipating into the atmosphere.

The evaporated gas adsorbed by the activated carbon 15 is transferred to the intake manifold 8 where negative pressure generated during engine 9 startup is transferred to the purge passage 7.
It is led to the pipe 5 of the canister 1 through the pipe 5 and is detached. At this time, the intake manifold 8 receives negative pressure, the check valve 3 closes, the check valve opens, and the atmosphere is introduced into the canister 1. The vaporized gas adsorbed by the activated carbon 15 in this atmospheric flow is desorbed, guided from the pipe 5 through the purge passage 7 to the intake manifold 8, and burned in the combustion chamber of the engine 9. As a result, the activated carbon 15 returns to its initial non-adsorption state and becomes ready for the next refueling.

〔Effect of the invention〕

According to the present invention, immediately after gasoline refueling, when the engine 9 is started and the canister 1 is in a detached state, the evaporated gas floating in the intake side space is not directly led to the intake manifold 8, but is instead passed through the 15 layers of activated carbon. The evaporated gas is guided to the intake manifold 8 in a state where the concentration of evaporated gas is reduced. Therefore, it is not necessary to send an excessive amount of evaporated gas to the intake manifold 8, and the engine speed and exhaust gas emissions can be stabilized.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of an embodiment of the present invention, and FIG. 2 is a longitudinal sectional view showing an embodiment of a canister according to the present invention. 1... Canister, 2, 3... Check valve, 4, 5...
・Pipe, 6...Evaporative gas passage, 7...Purge passage, 8...Intake manifold, 9...Engine, 10...Gasoline tank, 11...Gasoline inlet, 12... Air valve, 13, 18... Perforated plate, 14.17... Filter, 15... Activated carbon, 16
...Case, 19...Spring, 2o...Cover.

Claims (1)

[Claims] 1. An on-board regulation canister characterized by having an activated carbon layer sandwiched between the suction side and the desorption side of evaporated gas.