JPH0960558A - Gas engine carburetor - Google Patents

Abstract

(57) [Summary] [Solution] A lower end opening portion 6 of a main nozzle insertion tube 5
The mounting boss 12 of the cut solenoid 11 is fitted into and fixed to the needle boss 12, the needle valve 13 is projected upward from the mounting boss 12, and the inlet 14 of the main nozzle 7 can be opened and closed by raising and lowering the needle valve 13. Mounting boss 1 for the cut solenoid 11 in the carburetor
A frustum portion 15 is provided on the upper part of 2, and a portion 17 of the tip surface 16 of the main jet 8 which is directed into the main nozzle insertion tube 5 and which is lower than the measuring hole 9 is exposed to the peripheral surface 18 of the frustum portion 15. . [Effect] When gasoline is drained from the drain hole 10, an extremely small amount of gasoline 19 remains in a slight gap around the frustum 15 at the inner bottom portion of the main nozzle insertion tube 5 which is lower than the metering hole 9 of the main jet 8. Even if the gasoline 19 is gummed over time, the amount is extremely small, so that the metering hole 9 of the main jet 8 is unlikely to be clogged.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a carburetor for a gasoline engine, and more particularly to a carburetor capable of reducing gasoline remaining at the inner bottom of a main nozzle insertion cylinder when the gasoline is drained from a drain hole.

[0002]

2. Description of the Related Art A conventional carburetor for a gasoline engine is shown in FIG. This has the following basic structure as in the present invention.

That is, a float chamber 103 is provided below a mixing body 102 having a venturi portion 101 therein, and the bottom wall 1 of the float chamber 103 from the venturi portion 101 is provided.
The main nozzle insertion tube 105 is hung up to 04, and the main nozzle 107 inserted from the lower end opening 106 of the main nozzle insertion tube 105 is inserted into the main nozzle insertion tube 1
The main jet 108 is fixed laterally to the main nozzle insertion tube 105 at a position lower than the main nozzle 107, and the float chamber 103 and the inside of the main nozzle insertion tube 105 are communicated with each other through the measurement hole 109 of the main jet 108. A drain hole 110 is provided in the float chamber 103 at a position lower than the measuring hole 109 of the main jet 108 so as to be openable and closable.

Then, the mounting boss 112 of the cut solenoid 111 is fitted and fixed in the lower end opening 106 of the main nozzle insertion tube 105, and the needle valve 113 is projected upward from the mounting boss 112, and the needle valve 113 is raised and lowered. The inlet 114 of the main nozzle 107 can be opened and closed.

When this type of carburetor is mounted on a machine such as a rice transplanter that is used less frequently, the carburetor is left unused for a long time until the next use.
The gasoline is drained from the tank so that the metering hole 109 of the main jet 108 is not clogged due to the gumming of the gasoline over time. Further, when the ignition plug is misfired to stop the engine, the needle valve 113 simultaneously closes the inlet 114 of the main nozzle 107, and the main nozzle 10 is pumped by the piston during engine inertia rotation.
It prevents the gasoline from being sucked out from 7, and prevents the out-of-cylinder explosion caused by the introduction of the gasoline into the exhaust muffler.

In this conventional technique, the main jet 108 is used.
To the inner surface of the main nozzle insertion tube 105,
The mounting boss 112 of the cut solenoid 111 avoids interference with the main jet 108.
It is arranged at a position lower than 8.

[0007]

In the above prior art, even if the gasoline is drained from the drain hole 110, a relatively large amount of gasoline 119 remains on the inner bottom portion of the main nozzle insertion tube 105 lower than the metering hole 109 of the main jet 108. Therefore, the metering hole 109 of the main jet 108 may be clogged due to the gumming of many gasolines 119 with time.

An object of the present invention is to provide a carburetor for a gasoline engine capable of reducing the amount of gasoline remaining on the inner bottom portion of the main nozzle insertion cylinder when the gasoline is drained from the drain hole.

[0009]

As shown in FIG. 1, the present invention has the following basic structure. That is, the float chamber 3 is provided in the lower part of the mixing body 2 in which the venturi portion 1 is installed, the main nozzle insertion boss 5 is vertically provided from the venturi portion 1 to the bottom wall 4 of the float chamber 3, and the lower end of the main nozzle insertion tube 5 is provided. The main nozzle 7 inserted through the opening 6 is fixed to the upper part of the main nozzle insertion tube 5, the main jet 8 is attached sideways to the main nozzle insertion tube 5 at a position lower than the main nozzle 7, and the measurement hole 9 of the main jet 8 is attached. The float chamber 3 and the main nozzle insertion boss 5 are communicated with each other through a drain hole 10 which is openable and closable in the float chamber 3 at a position lower than the measuring hole 9 of the main jet 8.

Then, the mounting boss 12 of the cut solenoid 11 is fitted into and fixed to the lower end opening 6 of the main nozzle insertion tube 5, and the needle valve 13 is projected upward from the mounting boss 12 so that the needle valve 13 can be raised and lowered. The inlet 14 of the main nozzle 7 can be opened and closed.

The present invention is characterized by the following in a carburetor for a gasoline engine having the above-mentioned basic structure. That is, the frustum portion 15 is provided above the mounting boss 12 of the cut solenoid 11, and the portion 17 of the tip surface 16 of the main jet 8 facing the inside of the main nozzle insertion tube 5 that is lower than the measuring hole 9 is frustum portion 15. Surface 1
It is characterized by having faced 8.

[0012]

According to the present invention, when gasoline is drained from the drain hole 10, a slight gap around the frustum portion 15 is formed in the inner bottom portion of the main nozzle insertion tube 5 which is lower than the metering hole 9 of the main jet 8. Only a very small amount of gasoline 19 remains, and even if the gasoline 19 is gummed over time, the amount is extremely small, so that the metering hole 9 of the main jet 8 is unlikely to be clogged.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings. The carburetor of the gasoline engine shown in FIG. 1 has a mixing body 2 in which a venturi portion 1 is installed.
Is provided with a float chamber 3 in the lower part, a main nozzle insertion boss 5 is hung from the venturi portion 1 to the bottom wall 4 of the float chamber 3, and the main nozzle 7 inserted from the lower end opening 6 of the main nozzle insertion tube 5 is the main nozzle. The main jet 8 is fixed to the upper part in the insertion tube 5, and the main jet 8 is laterally attached to the main nozzle insertion tube 5 at a position lower than the main nozzle 7, and the inside of the float chamber 3 and the main nozzle insertion boss 5 are inserted through the measurement holes 9 of the main jet 8. The float chamber 3 at a position lower than the measuring hole 9 of the main jet 8.
A drain hole 10 is provided in the open / close state.

Then, the mounting boss 12 of the cut solenoid 11 is fitted and fixed in the lower end opening 6 of the main nozzle insertion tube 5, the needle valve 13 is projected upward from the mounting boss 12, and the needle valve 13 is raised and lowered. The inlet 14 of the main nozzle 7 can be opened and closed.

When it is mounted on a machine that is relatively infrequently used such as a rice transplanter, it will be unused for a long time until the next use. Therefore, the gasoline is drained from the drain hole 10 and the main jet is formed by gumming the gasoline over time. 8 measuring holes 9
Be careful not to clog. Further, when the ignition plug is misfired to stop the engine, the needle valve 13 simultaneously closes the inlet 14 of the main nozzle 7, and gasoline is sucked out from the main nozzle 7 by pumping the piston during engine inertia rotation. To prevent the out-of-cylinder explosion caused by the introduction of gasoline into the exhaust muffler.

The mixing body 2 includes a venturi portion 1
A choke valve 20 is provided on the upper side of the flow path of the above, and a throttle valve 21 is provided on the lower side of the flow path of the venturi portion 1. Reference numeral 26 in the figure indicates the intake direction. The lower end of the main nozzle insertion tube 5 is in contact with the bottom wall 4 of the float chamber 3 from above. The main jet 8 has a tubular shape, and a measuring hole 9 is provided at the center thereof, and is fixed to the nozzle insertion tube 5 from the side thereof by screw fitting. A manual opening / closing valve 22 is provided in the drain hole 10, and when the manual opening / closing valve 22 is opened, the gasoline in the float chamber 3 is discharged from the drain hole 10, and the gasoline in the main nozzle insertion tube 5 is discharged into the metering hole 9 of the main jet 8.
After flowing out from the to the float chamber 3, it is discharged from the drain hole 10.

The mounting boss 12 of the cut solenoid 11 is fixed to the opening at the lower end of the main nozzle insertion tube 5 by screw fitting. A valve seat 23 is provided below the main nozzle 7,
The needle valve 13 is seated on the valve seat 23.

In this embodiment, when the gasoline is drained from the drain hole 10, the frustum portion 15 is provided above the mounting boss 12 of the cut solenoid 11 in order to reduce the gasoline remaining in the inner bottom portion of the main nozzle insertion tube 5. Of the tip surface 16 of the main jet 8 that is provided and directed toward the inside of the main nozzle insertion tube 5, a portion 17 that is lower than the measuring hole 9 is provided in the frustum portion 1.
It faces the peripheral surface 18 of No. 5.

With this structure, when gasoline is drained from the drain hole 10, a slight gap around the frustum portion 15 is formed in the inner bottom portion of the main nozzle insertion boss 5 lower than the metering hole 9 of the main jet 8. Very small amount of gasoline 19
However, even if this gasoline 19 is gummed over time, the amount is extremely small, so the main jet 8
Clogging of the measuring hole 9 is unlikely to occur.

The frustum portion 15 is formed as a truncated cone. In order to make the gap around the frustum 15 smaller, the horizontal line 25
The elevation angle 24 of the peripheral surface 18 is preferably 45 ° or more, more preferably 60 ° or more, and most preferably 75 ° or more.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a carburetor according to an embodiment of the present invention, FIG. 1 (A) is a longitudinal sectional view, and FIG.
It is a B section enlarged view of (A).

FIG. 2 is a diagram illustrating a carburetor according to a conventional technique,
FIG. 2A is a vertical sectional view and an enlarged view of a portion B in FIG. 2A of FIG. 2B.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Venturi part, 2 ... Mixing body, 3 ... Float chamber, 4 ... Bottom wall, 5 ... Main nozzle insertion cylinder, 6 ... Lower end opening part, 7 ... Main nozzle, 8 ... Main jet, 9
… Measuring hole, 10… Drain hole, 11… Cut solenoid,
12 ... Mounting boss, 13 ... Needle valve, 14 ... Inlet, 15
... frustum portion, 16 ... tip end surface, 17 ... portion lower than measuring hole, 18 ... peripheral surface.

Claims (1)

[Claims] 1. A main nozzle is provided from a venturi (1) to a bottom wall (4) of the float chamber (3) by providing a float chamber (3) at a lower part of a mixing body (2) having the venturi part (1) installed therein. Insert the insertion tube (5) vertically, and insert the main nozzle insertion tube (5).
The main nozzle (7) inserted through the lower end opening (6) of the main nozzle is fixed to the upper part of the main nozzle insertion tube (5), and the main nozzle insertion tube (5) is positioned lower than the main nozzle (7).
The main jet (8) is installed sideways on the main jet (8), and the float chamber (3) and the main nozzle insertion tube (5) are communicated with each other through the measuring hole (9) of the main jet (8).
A drain hole (10) is openably and closably provided in the float chamber (3) at a position lower than the measuring hole (9) of (8), and a cut solenoid (11) is provided at a lower end opening (6) of a main nozzle insertion tube (5). ) Mounting boss (12) is inserted and fixed,
A needle valve (13) is projected upward from the mounting boss (12), and the inlet (14) of the main nozzle (7) can be opened and closed by raising and lowering the needle valve (13). A frustum portion (15) is provided on an upper portion of a mounting boss (12) of a solenoid (11), and a measuring hole is provided on a tip surface (16) of a main jet (8) directed into a main nozzle insertion tube (5).
The part (17) lower than (9) is the peripheral surface (18) of the frustum part (15).
A carburetor for a gasoline engine, characterized in that