JPS5842598Y2 - Fuel vapor processing equipment for internal combustion engines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fuel vapor processing device for discharging fuel vapor generated from a carburetor to the outside of an intake system when an engine is stopped.

In the summer or after continuous high-load operation, the inside of the engine compartment becomes quite hot.

This is particularly high for engines that maintain exhaust gas at a high temperature to purify the exhaust gas. Under such high-temperature conditions, after the engine is stopped, radiant heat in the engine room and heat transfer from the engine cause vaporization. Fuel vaporizes from the float chamber of the vessel and becomes steam, which rises through the vent pipe and collects in the suction passages and suction systems such as air cleaners.

Furthermore, the residual air-fuel mixture in the suction pipe and air-fuel mixture passage is also vaporized, rises in the suction passage, and accumulates in the air cleaner.

For this reason, if the engine is restarted soon after it has been stopped, the accumulated steam will be sucked into the engine, making the air-fuel mixture too rich and difficult to ignite, resulting in failure to start.

However, as an example of prior art that addresses this drawback, there is a technique disclosed in Japanese Patent Publication No. 48-41162, which states that the above-mentioned fuel vapor contains carbon particles from the air cleaner. However, the problem is that the structure is complicated and uneconomical.

The present invention is an attempt to solve the above-mentioned drawbacks and problems.The device has a hole for removing fuel vapor in the lower part of the air cleaner case, and through the hole, fuel vapor enters the intake system when the engine is stopped. In addition to discharging the fuel vapor to the outside, the discharged fuel vapor is cooled by a cooling device with an extremely simple structure such as a heat dissipating bellows section or a heat dissipating fin section, and then guided to a storage section where it can be stored. This is a characteristic feature.

Hereinafter, an actual case of the present invention will be explained in detail with reference to the drawings.

In the figure, 1 is an engine blower (not shown);
2 is an intake pipe, and 3 is a float chamber of a carburetor. When the engine is stopped, fuel vapor vaporized in the float chamber 3 passes through a vent pipe 4 and enters an intake passage 5, and further rises within this passage 5. and enter air cleaner 6.

However, in the present invention, the case 6 of the air cleaner 6
A hole 7 is provided at the lower part of the hole 7, and this hole 7 is communicated with a storage box 9 located below the hole 7 through a pipe 8.
A filter 10 is interposed in the middle of the storage box 9, and a bellows part 11 for heat radiation is formed in a part thereof as a cooling device for the fuel vapor, or a heat radiation fin part is provided. A horizontal partition wall 13 is provided, leaving a communication portion 12 in a part, and a ventilation hole 14 is provided in the upper chamber so as to open to the atmosphere.

Note that the diameter of the hole 7 is preferably about 14 mm.

According to such a configuration, the fuel vapor rising in the air cleaner 6 is heavier than air, and therefore flows out from the hole 7 at the bottom of the case 6a, and flows into the pipe 8, its heat radiation bellows 11, or its heat radiation fin portion. The liquid flows through the storage box 9 and is stored in the storage box 9 while being actively cooled and accelerated.

The liquefied fuel is accumulated in the lower chamber of the storage box 9, and the separated air enters the upper chamber, from which it is discharged into the atmosphere through the vent hole 14.

By doing so, it is possible to prevent fuel vapor from dissipating into the atmosphere and polluting the air.

After the engine is restarted, the fuel gas accumulated in the storage box 9 is gradually passed through the filter 10 by suction negative pressure and is again sucked into the carburetor 1 and used for harmonic combustion. It may be taken out at a certain time.

As is clear from the above, according to the present invention, the fuel vapor generated from the carburetor when the engine is stopped is removed from the intake system, so it is possible to solve and eliminate the drawbacks of conventional methods that cause startup failure when the engine is restarted. The fuel vapor is actively cooled by a cooling device, which has a much simpler structure than the adsorption device of the prior art, such as a heat-radiating bellows portion or a heat-radiating fin portion, to promote liquefaction and is stored in a storage portion.
The separation of the air is accelerated, the fuel vapor does not dissipate into the atmosphere and pollute the air, and the fuel gas thus accumulated in the reservoir is gradually transferred to the carburetor after the engine is restarted. Since it is inhaled and used for combustion, there is no loss of fuel.

[Brief explanation of drawings]

The drawing is a sectional view showing an example of the present invention. 1... vaporizer, 2... suction pipe, 3...
... Float chamber, 4 ... Vent pipe, 5
...Suction passage, 6...Air cleaner,
7...hole, 8...tube, 9...
Storage box, 10...Filter, 11...
Heat dissipation bellows part, 12...Communication part, 13...
...Partition wall, 14...Vent hole.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A fuel vapor exhaust hole is provided in the lower part of the air cleaner, and a cooling device such as a heat dissipating bellows part or a heat dissipating fin part is provided to connect the reading plate and the storage section located below it. □ A fuel vapor processing device for an internal combustion engine, characterized in that the fuel vapor is communicated with the storage portion through a pipe line, and the fuel vapor is stored in the storage portion. 2. The fuel vapor processing device for an internal combustion engine as claimed in claim 1 of the Utility Model Registration Claim, which has a horizontal partition wall in the storage section and a ventilation hole in the upper part.