JPS6016766Y2 - Automotive evaporative loss prevention device - Google Patents

Description

[Detailed description of the invention] This invention relates to prevention of separation of alcohol and gasoline due to water contamination in alcohol blended gasoline.

As a conventional evaporative fuel loss prevention device (so-called evaporative loss prevention device), there is one shown in Fig. 1 (for example, 197 (4 DATSUN published by Nissan Motor Co., Ltd.).
B2105service Manua1 etc.).

Reference numeral 1 designates a fuel tank in which fuel evaporates during operation or stoppage, and is temporarily stored in a canister 13 through a vapor passage 4 passing through a check valve 3.

During operation, a negative pressure signal from the intake pipe 8 is guided through the canister signal passage 5, and the temporarily stored evaporated fuel passes through the canister purge passage 6 and enters the combustion chamber from the intake pipe 8 and is burned.

When the temperature drops after stopping, the evaporated fuel liquefies,
The pressure inside the tank decreases and fresh air is introduced into the tank 1 through the fresh air inlet 13'.

In the figure, 2 is a fuel inlet, 7 is an air cleaner, and 9 is a fuel inlet.
1 is an exhaust pipe, 10 is an EGR pipe, 11 is an EGR controller, and 12 is an engine body.

Further, in the canister 13, 13a is a bottom plate, which guides engine suction negative pressure generated in the caster signal passage 5 while the engine is running to the valve 13b, and directs it to the canister purge passage 6.
The engine is opened to introduce negative intake pressure of the engine to the canister 13, and air is sucked in through a number of small holes provided in the canister bottom plate 13a, thereby purging the evaporated fuel accumulated in the canister.

13c is a filter.

In the above-mentioned conventional evaporative fuel loss prevention device equipped with the canister 13, fresh air is introduced directly from the outside, so moisture in the atmosphere enters the fuel tank, causing alcohol-blend gasoline to enter the fuel tank. Separates into alcohol and gasoline (for example, gasoline containing 10% methanol at 201° C. is separated into alcohol and gasoline with 0.15% water).

This idea was devised by focusing on these conventional problems, and has a structure in which a moisture removal device made of heat-renewable alumina gel or the like is interposed in the fresh air introduction passage to introduce fresh air into the canister. , moisture is removed from fresh air when the engine is stopped, and the removed moisture is released using exhaust heat during operation.

This invention will be explained below based on the drawings.

FIG. 2 is a diagram showing an embodiment of this invention.

First, to explain the structure, numerals 1 to 13 indicate the same structure as in FIG. 1, and the difference is that 14 is the canister bottom plate
It is a lid of a canister provided outside 3a, 15 is a fresh air introduction passage (purge air passage), and 16 is a moisture removal device, and a detailed view of the moisture removal device 16 is shown in FIG.

Reference numeral 17 indicates a renewable moisture removing agent such as Alunagel, 18 indicates a wire mesh forming an air intake port, 19 indicates a case, 20 indicates a metal fitting for supporting the case, and 21 indicates a mounting metal fitting. A fuel loss prevention device (so-called evaporation loss prevention device) is formed.

Next, the action will be explained.

The function of the present invention is that when the temperature of the engine decreases after the engine is stopped, the evaporated fuel liquefies, the pressure inside the fuel tank 1 decreases, and air is introduced into the tank 1 through the fresh air introduction passage 15.

At this time, the moisture in the air is removed by passing it through alumina gel 17 or the like for removing moisture, thereby preventing separation of alcohol and gasoline due to moisture in the alcohol blend gasoline.

This moisture removal device 16 is attached to the EGR passage 10 (this embodiment), exhaust pipe, etc. where exhaust heat can be used, and during normal operation, the alumina gel 17 and the like are thermally regenerated using the exhaust heat.

In addition, adding an explanation about alumina gel, 175-3
Since it is regenerated at 20℃ and the gel state is broken at about 600℃,
Regeneration of exhaust heat uses EGR passage outer wall temperature of 100 to 300℃
It is best to use the exhaust pipe, and it is necessary to choose a location with a low temperature for the exhaust pipe.

As explained above, according to this invention, the structure uses a moisture removal device filled with a moisture removal agent such as alumina gel that can be thermally regenerated to remove moisture from the air introduced into the fuel tank. , the effect of preventing separation of alcohol and gasoline due to water contamination of gasoline in an alcohol blend can be obtained.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a conventional evaporative fuel loss prevention device, Fig. 2 is an explanatory diagram of an embodiment of the present invention, and Fig. 3 is a vertical sectional view of a moisture removal device that can be applied to the present invention. FIG. 1...Fuel tank, 4...Vapor passage, 5...K, Yanista signal passage, 6...
・Canister purge passage, 10... EGR piping, 13... Canister, 14... Lid, 15... Fresh air introduction passage, 16... ...Water removal device, 17...Renewable water removal agent such as alumina gel.

Claims (1)

[Scope of utility model registration request] In an evaporative fuel loss prevention device equipped with a canister for an automobile that uses fuel blended with gasoline and alcohol, a fresh air introduction passage connected to the canister of the evaporative fuel loss prevention device is formed to remove moisture from the atmosphere. An evaporative loss prevention device for an automobile, characterized in that a moisture removal device for removing moisture is interposed in the fresh air introduction passage.