JPS6211300Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an improvement of a blow-by gas recirculation device, and particularly to a blow-by gas recirculation device that recirculates blow-by gas into an intake air flow that does not flow into an air vent opening.

[Conventional technology]

Blowby gas is gas that leaks into the crankcase through gaps in the piston rings, and is returned to the intake system such as an air cleaner and combusted again to comply with exhaust gas regulations.

[Problem that the invention attempts to solve]

By the way, in conventional blow-by gas recirculation devices, if blow-by gas is recirculated into the intake system of an internal combustion engine without consideration, the air vent opening of the carburetor, the bleed air passage, the float chamber, the fuel in the float chamber, etc. , contaminants such as lubricating oil droplets and carbon in the blow-by gas may cause clogging, causing engine trouble.

Further, in order to avoid the above-mentioned disadvantages, there is a structure in which a shielding plate is provided in front of the blow-by gas recirculation port so that the blow-by gas is not blown directly over the entire vaporizer. (Jitsugan 51-
135784 Jitsukō 60-21460).

However, as the blow-by gas is blown against the shielding plate, the contaminants in the blow-by gas will accumulate and stick on the surface of the shielding plate and around the reflux port, which may eventually block the reflux port, causing vaporization. There is a disadvantage that it is not possible to maintain good performance of the engine, that is, the performance of the internal combustion engine.

[Purpose of invention]

Therefore, the purpose of this invention was to improve the air vent opening of the carburetor, the bleed air passage, the float chamber, and the fuel in the float chamber, which are frequently used in practical applications.
It prevents contaminants such as lubricating oil droplets and carbon in the blow-by gas, and prevents engine troubles such as clogging. It also makes it possible to clean the reflux port and its surroundings, preventing contaminants from accumulating and sticking. The goal is to realize a blow-by gas reflux device.

[Means for solving problems]

In order to achieve this purpose, this invention provides a recirculation mechanism that recirculates the blow-by gas into the intake air flow that does not flow into the air vent opening, and the recirculation opening of this recirculation mechanism is connected to the recirculation opening of the recirculation mechanism so that the atomized fuel from the nozzle of the carburetor accelerator pump It is characterized by being provided in a flow path area having a cleaning function.

[Effect]

With the above configuration, when the carburetor acceleration pump is in operation, fuel is ejected from the nozzle,
By directing the flow of blow-by gas in the intake passage in a predetermined direction, the recirculation port and its surroundings can be cleaned by the fuel spray, thereby preventing contaminants from accumulating and sticking.

〔Example〕

Embodiments of this invention will be described below based on the drawings. Figures 1 and 2 show an embodiment of this invention, in which 2 is a crankcase, 4 is a cylinder head cover, 6 is a breather pipe, 8 is a carburetor, and 10 is a cylinder head cover.
12 is an intake passage, 12 is a recirculation port, 14 is an air vent opening, 16 is a float chamber air vent, 18
is an air jet, 20 is a bleed air passage, 22
is a chiyoke valve, and 24 is an air cleaner. A separator (not shown) is provided at the top of the cylinder head cover 4 to separate lubricating oil droplets in the blow-by gas, and a breather pipe 6 is attached to the separator.
One end of the breather pipe 6 is connected to the other end of the recirculation port 12, as shown in FIG.
The opening 14 on the downstream side or upstream side of 4
The opening ends in a flow path region having a function of cleaning the sprayed fuel from the acceleration pump nozzle 30, which is a position exposed to the spray of the fuel sprayed from the acceleration pump nozzle 30 in the intake air flow C that is not directed toward the fuel. Further, a control valve 26 is interposed in the middle of the breather pipe 6 as necessary, and the control valve 26 is interlocked with a throttle valve (not shown) in the intake passage 10 to respond to the opening operation of the throttle valve. It is preferable that the control valve 26 is configured to be controlled to open.

Next, the effect will be explained. The blow-by gas refluxed from the reflux port 12 is sent to the combustion chamber through the intake passage 10, but the reflux port 12 is opened and ends in the passage area of the intake air flow C that does not flow into the air vent opening 14. Therefore, the problem of blow-by gas flowing into the air vent opening 14 does not occur. Therefore, float chamber air vent 1
6. Air jet 18, bleed air passage 20, etc. are not contaminated by contaminants in the blow-by gas, and clogging due to contaminants can be prevented, and engine troubles can be prevented.

In addition, the sprayed fuel from the nozzle 30 of the acceleration pump gives good directivity to the blow-by gas, and the sprayed fuel can clean the reflux port 12 and its surroundings, which is effective in preventing the accumulation and fixation of contaminants. can be prevented.

[Effect of idea]

As explained in detail above, according to this invention, the blow-by gas recirculation port is provided in the flow path area that has the function of cleaning the sprayed fuel from the nozzle of the carburetor accelerator pump, so that the fuel sprayed from the nozzle can
The flow of blow-by gas in the intake passage can be directed in a predetermined direction, although only when the pump is operating, and the recirculation port and its surroundings can be cleaned with this fuel spray, preventing contaminants from accumulating and sticking. This can contribute to maintaining good performance of the carburetor, that is, of the internal combustion engine.

In addition, since the blow-by gas is recirculated into the intake air flow without flowing into the air vent opening in the intake passage, precision mechanical parts such as the air vent opening, bleed air passage, float chamber, and fuel in the float chamber are , there is no inconvenience caused by contaminants such as lubricating oil droplets and carbon in blow-by gas,
It is possible to prevent engine troubles due to clogging of this precision mechanism part.

[Brief explanation of the drawing]

1 and 2 show an embodiment of this invention, with FIG. 1 being a schematic side view of a blow-by gas recirculation device, and FIG. 2 being an enlarged sectional side view of a main part of an intake passage. In the figure, 2 is the crankcase, 4 is the cylinder head cover, 6 is the breather pipe, 8 is the carburetor, 10 is the intake passage, 12 is the recirculation port, 14 is the air vent opening, and 30 is the nozzle of the carburetor acceleration pump. .

Claims (1)

[Scope of utility model registration request] A recirculation mechanism is provided to recirculate blow-by gas into the intake air flow that does not flow into the air vent opening, and the recirculation opening of this recirculation mechanism is provided in a flow path area where the sprayed fuel from the nozzle of the carburetor accelerator pump has a cleaning function. A blow-by gas recirculation device featuring: