JP2551480Y2 - Vaporizer with advanced mixing ratio correction function - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carburetor for an internal combustion engine, and more particularly to a carburetor provided with a valve capable of adjusting a mixing ratio by a change in atmospheric pressure.

[0002]

2. Description of the Related Art Conventionally, as an example of a carburetor 1 for an internal combustion engine of this type, there is a carburetor 1 shown in FIG. And a float chamber 2 for storing a fixed amount of water, a main jet 3 provided at the bottom of the float chamber 2 for measuring fuel, and a flow rate of air flowing into the engine. It comprises a venturi section 4 for creating a pressure for sucking out the corresponding fuel, and a main nozzle 5 for jetting the fuel into the airflow. The float chamber 2 is connected to the upstream side of the venturi section 4 via an air vent 6. ing.

[0003]

However, in the conventional vaporizer 1, since the diameter of the main jet 3 provided in the float chamber 2 is constant, the vaporizer 1 can be used in a place where the air density is low, such as a highland. Also, there is a problem that the same amount of fuel is sucked out with respect to the air flow rate, and the mixture ratio becomes high.

The present invention has been made to solve the above-mentioned conventional problems, and controls the fuel passage area of the main jet provided at the bottom of the float chamber in proportion to a change in the atmospheric pressure to thereby achieve the desired mixing. It is an object of the present invention to provide a vaporizer with an advanced mixing ratio correction function capable of obtaining a ratio.

[0005]

SUMMARY OF THE INVENTION In order to solve the above-mentioned technical problem, the present invention provides a vaporizer having a main jet disposed at the bottom of a float chamber, wherein a diaphragm is provided inside a diaphragm shell at an upper part of the float chamber. A diaphragm chamber and a diaphragm working chamber at the lower part are formed in a compartment, and a metering rod having a needle portion at a tip thereof is vertically provided on the diaphragm so as to be directed to the main jet,
The diaphragm working chamber is in a vaporizer with an advanced mixing ratio correction function configured to communicate with the atmosphere via an atmosphere passage and to displace the diaphragm in accordance with a change in air pressure to control the area of the main jet.

[0006]

With the above construction, the pressure at the altitude from the atmosphere passage acts on the diaphragm working chamber to displace the diaphragm, whereby the metering rod attached to the diaphragm is directed to the main jet, and the pressure is reduced to the atmospheric pressure. In addition to being held at a position corresponding to the needle, the needle portion at the tip faces the main jet, the area of which is increased or decreased according to the air pressure, so that a fuel amount corresponding to the altitude can be passed.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows a vaporizer 1 with an advanced mixing ratio correction function.
FIG. 1 is a cross-sectional view of a venturi section 14 (hereinafter simply referred to as a carburetor) and a float chamber 12. In order to supply a stable fuel to an engine as in the prior art, the fuel level is kept constant and the fuel level is kept constant. A float chamber 12 to be stored, a main jet 13 provided at the bottom of the float chamber 12 for measuring fuel, and calculating a flow rate of air flowing into the engine and sucking out fuel corresponding to the flow rate of the air. A venturi section 14 for creating pressure;
The float chamber 12 is connected to an upstream side of the venturi section 14 via an air vent 16. An altitude mixing ratio corrector 17 is provided above the float chamber 12 provided in this manner.

The high-mixing-ratio correction device 17 utilizes a diaphragm 19, and the diaphragm shell 1
The diaphragm 8 is divided into a diaphragm chamber 20 and a diaphragm working chamber 21 by a diaphragm 19, and the diaphragm working chamber 21 is communicated with the atmosphere through an atmosphere passage 22. Further, the diaphragm chamber 20 is provided with the diaphragm 19.
In the diaphragm chamber 20, a spring member 23 having a predetermined spring pressure is provided. The diaphragm chamber 20 is provided so as to maintain a balance when the pressure in the diaphragm working chamber 21 is the atmospheric pressure, that is, the horizon, and to hold the diaphragm 19 horizontally Ho.

In the center of the diaphragm 19, a metering rod 24 having a tapered needle portion 25 at the tip is provided.
The center of the metering rod 24 is aligned with and oriented to the center of the main jet 13. Metering rod 24 provided in this manner
The diaphragm 19 to which the pressure is applied detects the atmospheric pressure due to the altitude acting on the diaphragm working chamber 21 based on the sum of the internal pressure of the diaphragm chamber 20 and the spring pressure of the spring member 23, and the altitude-atmospheric pressure, altitude-atmospheric specific weight. As shown by a dashed line in the drawing based on a diagram (not shown), the displacement Hm is stepwise, and the area of the main jet 13 is controlled to control the enrichment ratio of the high mixing ratio.

[0010] Since it is configured as described above,
When the vehicle travels on level ground, the internal pressures of the diaphragm chamber 20 and the diaphragm working chamber 21 are balanced as in the prior art, the diaphragm 19 is kept horizontal, and the needle 25 of the metering rod 24 is held at the position Ho. A constant fuel amount is drawn from the main nozzle 15 from the main jet 13 in accordance with the air flow rate of the venturi section 14.

When the vehicle is traveling at high altitude, the air passage 2
The diaphragm 19 is displaced in a state shown by a broken line in the drawing by acting on the diaphragm working chamber 21 by the air pressure at the altitude from the altitude 2, whereby the metering rod 24 attached to the diaphragm 19 is directed to the main jet 13 and lowered to the displacement Hm shown in the drawing. The needle 25 at the tip faces the main jet 13 so that the area thereof is reduced according to the air pressure, and the fuel amount according to the altitude is passed.

[0012]

According to the present invention, a vaporizer having a main jet disposed at the bottom of a float chamber is provided with a diaphragm in a diaphragm shell at an upper part of the float chamber, and a diaphragm chamber at an upper part and a diaphragm working chamber at a lower part. A partition is formed, and a metering rod having a needle portion at the tip thereof is vertically provided on the diaphragm to be directed to the main jet, and the diaphragm working chamber communicates with the atmosphere through an atmosphere passage to change the air pressure. Because the diaphragm is displaced to control the area of the main jet, the air-fuel mixture becomes too rich even when traveling at high altitude, the engine malfunctions, and exhaust regulations cannot be satisfied. The problem is solved, and it can be used not only on flat ground but also on high ground.

[Brief description of the drawings]

FIG. 1 is a sectional view of a venturi section and a float chamber in a vaporizer.

FIG. 2 is an enlarged sectional view of an altitude mixing ratio correction device.

FIG. 3 is a sectional view of a venturi section and a float chamber in a conventional vaporizer.

[Explanation of symbols]

 11 Vaporizer with advanced mixing ratio correction function 12 Float chamber 13 Main jet 17 Advanced mixing ratio correction device 18 Diaphragm shell 19 Diaphragm 20 Diaphragm chamber 21 Diaphragm working chamber 22 Atmospheric passage 24 Metering rod 25 Needle

Claims (1)

(57) [Scope of request for utility model registration] 1. A vaporizer in which a main jet is disposed at the bottom of a float chamber, wherein a diaphragm is provided inside a diaphragm shell at an upper part of the float chamber, and a diaphragm chamber is formed at an upper part and a diaphragm working chamber is formed at a lower part. Along with vertically suspending a metering rod having a needle portion at the tip thereof, directed to the main jet,
A vaporizer with an advanced mixing ratio correction function, wherein the diaphragm working chamber communicates with the atmosphere via an atmosphere passage and displaces the diaphragm in accordance with a change in air pressure to control the area of the main jet.