JPS5833390B2 - torch tenka engine yokikaki - Google Patents

Description

Detailed Description of the Invention The present invention forms a rich mixture portion and a lean mixture portion in the fuel chamber, and ignites the lean mixture with the combustion flame generated by igniting the rich mixture with a spark plug. The present invention relates to a torch ignition engine carburetor that is used in a so-called stratified combustion internal combustion engine, and includes a sub-carburetor that supplies the rich air-fuel mixture and a main carburetor that supplies the lean air-fuel mixture.

In general, stratified combustion internal combustion engines dilute the intake air-fuel mixture throughout the engine, and the exhaust gas contains NOx (nitrogen oxides) and C0 (-
It reduces carbon oxide), HC (hydrocarbon), etc.
As an example, a torch-ignited internal combustion engine has been proposed, which consists of a main combustion chamber to which a lean air-fuel mixture is supplied, and an auxiliary combustion chamber that communicates with this through a torch hole and is supplied with a rich air-fuel mixture and is equipped with an ignition plug. There is.

This torch-ignited internal combustion engine blows a combustion flame formed in a sub-combustion chamber into a main combustion chamber through a torch hole to ignite and burn a lean air-fuel mixture within the main combustion chamber.

Such a torch-ignited internal combustion engine is equipped with an auxiliary carburetor that supplies a rich mixture to the auxiliary combustion chamber and a main carburetor that supplies a lean mixture to the main combustion chamber, but these are integrated and Preferably, each float chamber is supplied with fuel.

In other words, this is to minimize engine layout problems and link-specific integration errors that determine the correspondence between the main and auxiliary carburetors.

Furthermore, sharing the float chamber is for the purpose of simplifying the entire carburetor for a torch ignition engine by reducing the number of components.

However, when configuring the carburetor for a torch ignition engine in this way, the problem is fluctuations in the fuel oil level in the float chamber.

It is generally known that harmful components emitted from this type of torch-ignited internal combustion engine are affected by the main combustion chamber.

In other words, the volume of the main combustion chamber is much larger than that of the auxiliary combustion chamber, so no matter how lean the air-fuel mixture supplied to the main combustion chamber is, the fuel flow rate per cycle is much higher in the main combustion chamber. This is because there are many

Therefore, the mixture ratio of the air-fuel mixture supplied to the main combustion chamber (♀'E
icR equipment) must be highly controlled.

Due to the fuel flow rate and the nature of engines installed in automobiles, which perform sudden turns and sudden acceleration/deceleration, the oil level in the float chamber of the carburetor fluctuates, causing the mixture ratio of the air-fuel mixture supplied to the engine to change.

Therefore, it is necessary to arrange the float chamber approximately near the center of the main carburetor to eliminate the influence of the tilt of the vehicle.

However, if the float chamber is placed near the center of the main carburetor, when the car makes a sharp turn or accelerates or decelerates suddenly, the air-fuel mixture supplied from the auxiliary carburetor will be affected by oil level fluctuations and become overly rich. .

For this reason, if the mixture becomes too rich, the spark plug installed in the auxiliary combustion chamber will heat up the fuel, making it impossible to generate flame in the auxiliary combustion chamber, and making it impossible to combust the air-fuel mixture in the main fuel chamber. .

Therefore, harmful components, particularly HC, in the exhaust gas increase rapidly, resulting in an unfavorable result in terms of exhaust gas regulations.

Additionally, in order to reduce the effects of oil level fluctuations, it is possible to place both the main fuel nozzles of the main and sub-carburetors at higher positions than conventional ones (in this case, the float chamber can be placed at any position). I can do it.

), this will cause problems such as a delay in fuel supply and failure to satisfy the engine's required mixture.

In other words, if conventional air bleeds, fuel jets, etc. are used as they are, the main fuel nozzle will be higher and the fuel will be delayed.

Furthermore, if the air bleed, fuel jet, venturi diameter, etc. are changed to eliminate the fuel start-up delay, the mixture ratio and amount of the mixture supplied to the engine will differ from the engine's required values.

In particular, if the air-fuel mixture supplied to the main fuel chamber is not highly controlled as described above, it will be extremely disadvantageous in terms of exhaust emissions.

SUMMARY OF THE INVENTION An object of the present invention is to provide a carburetor for a torch ignition engine that can supply a good air-fuel mixture to the engine by minimizing the effects of oil level fluctuations in the float chamber on the auxiliary carburetor and the main carburetor. be.

A feature of the present invention is that the sub-carburetor and the main carburetor are integrated, the float chamber is arranged at a position such that the center of inclination of the float chamber is near the center line of the main fuel nozzle of the main carburetor, and A part of the main fuel passage including the main fuel nozzle opening of the carburetor is arranged at a higher position than the main fuel nozzle opening of the main carburetor, so that even if the oil level in the float chamber fluctuates, the main fuel passage and the sub-vaporizer It is designed to minimize the effects of this on the vessel.

Reference numeral 1 denotes a torch ignition engine carburetor, which is composed of a main carburetor 2 and an auxiliary carburetor 3.

The main carburetor 2 is a compound type having a primary side 4 and a secondary side 5, and a primary venturi 6 and a secondary venturi 7 are formed on each side.

- On the next side 4, there is a choke valve 8, a main air bleed 9, an emulsion tube 10, etc., and a primary side main fuel passage 11, - a next side main fuel nozzle 12, and an idle adjustment screw (not shown), etc. A low speed system is provided.

Further, on the secondary side 5, there are a secondary main fuel passage 15 and a secondary main fuel nozzle 16 which are composed of a main air bleed 13, an emulsion tube 14, etc., and a step jet 17 branched from the secondary main fuel passage 15. , step air bleed 1
A step passage 19 composed of 8 etc. is provided.

The above-mentioned primary side main fuel passage 11, low speed system (not shown), secondary side main fuel passage 15, and step passage 19 are each communicated with a float chamber 20 shown by a broken line.

This float chamber 20 is filled with fuel, and the fuel is maintained at a substantially constant oil level by a float device (not shown).

As can be seen from the drawing, the center of inclination of the float chamber 20 is located approximately in the middle of the main carburetor 2, that is, at a position that approximately coincides with the center line between the primary side main fuel nozzle 12 and the secondary side main fuel nozzle 16. There is a head difference of H between the constant oil level of the float chamber 20 and the primary and secondary nozzles 12°16.

Next, the air-fuel mixture in the main carburetor 2 is controlled by a primary throttle valve 21 and a secondary throttle valve 22 provided respectively.

Here, the secondary throttle valve 22 is configured to open when the primary throttle valve 21 is opened by a predetermined amount.

Next, the configuration of the sub-carburetor 3 will be explained. The sub-carburetor 3 is integrated with the main carburetor 2 and is disposed adjacent to the downstream side 4, with a by-product fuel passage 23, an auxiliary low-speed fuel passage 24, , sub-throttle valve 2
5.

The by-product fuel passage 23 is composed of a main air bleed 26, an emulsion tube 27, etc., one of which opens into the float chamber 20, and the other opens into the venturi 28 through a by-product fuel nozzle 29.

The auxiliary low speed passage 24 is composed of a low speed air bleed 30, a low speed jet 31, etc., and one side of this also opens into the float chamber 20,
The other side opens downstream of the sub-throttle valve 25.

An idle adjustment screw 32 is provided in the auxiliary low-speed passage 24 that opens downstream of the auxiliary throttle valve 25, and is adapted to adjust the fuel during idling.

The auxiliary throttle valve 25 is connected to the adjacent primary throttle valve 21 and the rod 3.
3, so that the sub-throttle valve 25 is displaced in accordance with the displacement of the primary-side throttle valve 21.

As is clear from the drawing, the horizontal passage 2 forming the auxiliary main fuel nozzle 29 and the auxiliary low-speed fuel passage 24 of the auxiliary carburetor 3
41 has a head difference Hl from the constant oil level of the float chamber 20, and this head difference H1 has the relationship Hl>H.

In the above, the operation will be explained next.

When the primary throttle valve 21 is opened to start the engine, the auxiliary throttle valve 25 is opened via the rod 33, and fuel is injected from the downstream main fuel nozzle 12 and the auxiliary main fuel nozzle 29 and supplied to the engine. be done.

(Before this, it goes without saying that the primary and secondary low-speed systems were operating.

) Then, when the primary throttle valve 21 opens further, the secondary throttle valve 22 opens.
starts to open, fuel is supplied from the step passage 19 and the secondary side main fuel passage 15, and the secondary side 4 is activated.

In such a vehicle, when the gold-plated vehicle makes a sudden turn, accelerates or decelerates suddenly, the oil level in the float chamber 20 becomes c - c' with respect to the center of inclination O.

There is a phenomenon that fluctuates like the D-D' line.

This causes a variation in the mixture ratio of the lean mixture supplied to the main fuel chamber, but in the present invention, since the float chamber 20 is disposed approximately in the middle of the main carburetor 2, the primary and secondary The influence of oil level fluctuations on the side main fuel nozzles 12.16 can be minimized.

That is, since the secondary main fuel nozzles 12 and 16 are provided closest to the center of inclination O of the float chamber 20, even if the oil level fluctuates, the influence of the fluctuation is minimized.

Therefore, it becomes possible to optimally supply the air-fuel mixture to the main combustion chamber, which influences the harmful components emitted from the entire engine.

On the other hand, in the auxiliary carburetor 3, the auxiliary main fuel nozzle 29 and the horizontal passage 241 of the auxiliary low-speed passage 24 are located at a higher position than the primary and secondary main fuel nozzles 12, 16, so the oil level is like the line DD'. Even if it fluctuates, its influence will be minimal, and no excess fuel will be supplied from the sub-main fuel nozzle 29 and the sub-low-speed passage 24.

Therefore, a good air-fuel mixture is supplied to the sub-combustion chamber, the ignition plug is not heated by the fuel, and the air-fuel mixture in the sub-combustion chamber can be sufficiently ignited.

In this way, in this example, the influence of oil level fluctuations on the auxiliary carburetor and main carburetor is minimized, making it possible to supply a good air-fuel mixture to the main and auxiliary combustion chambers, and to obtain good exhaust characteristics. .

In the embodiment, the main carburetor is of a dual type, but may be of a single-shell type, and in this case, the center of inclination of the float chamber may be placed on the mass center line of the single-shell type.

Although the auxiliary carburetor is provided with a auxiliary low-speed passage, in the case where the auxiliary low-speed passage is not provided, only the auxiliary main fuel nozzle may be arranged at a high position.

Next, a second embodiment of the present invention will be described based on FIG.

In the system shown in FIG. 2, a part of the by-product fuel passage 23 and the auxiliary low-speed passage 24 leading to the auxiliary main fuel nozzle 29 are arranged at a higher position than the main fuel nozzles 12 and 16 of the main carburetor 2. This was done to eliminate the impact.

That is, the pipe 34 is connected to the vertical passage 2 of the by-product fuel passage 23.
31, and the pipe 35 is connected to the vertical passage 242 of the auxiliary low-speed passage.
The pipes 34 and 35 are arranged so as to have a head difference of H2 with respect to the primary fuel nozzle 12.

Therefore, even if the oil level fluctuates as shown in Figure 1, the tilting performance will improve by the head difference H2, and even if the car tilts, no excess fuel will be supplied and a good mixture can be supplied to the sub-combustion chamber. .

As described above, according to the present invention, it is possible to minimize the influence of oil level fluctuations on the main carburetor and the sub-carburetor, thereby making it possible to obtain good exhaust characteristics.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a carburetor for a torch-ignited engine according to an embodiment of the present invention, and FIG. 2 is a longitudinal cross-sectional view of essential parts of a rigid carburetor for a torch-ignited engine according to a second embodiment of the present invention. . 2... Main carburetor, 3... Sub carburetor, 12... Next side main fuel nozzle, 20... Float, 29... Sub main fuel nozzle, O... Center of inclination.

Claims (1)

[Claims] 1. A torch ignition system that integrates an auxiliary carburetor that supplies a rich air-fuel mixture to a combustion chamber and a main carburetor that supplies a lean air-fuel mixture, and that supplies fuel to the carburetor from a single float chamber. In a carburetor for an engine, the float chamber is provided almost in the middle of the main carburetor side, and a main fuel nozzle opening of the sub carburetor or a part of the passage leading to the main fuel nozzle opening is connected to the main fuel nozzle opening of the sub carburetor. A carburetor for a torch ignition engine, characterized in that it is arranged at a higher position than the opening of a fuel nozzle.