JP2554902Y2 - Vaporizer acceleration pump device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an acceleration pump device for a vaporizer.

[0002]

2. Description of the Related Art Conventionally, an acceleration pump device reduces the volume of a pump chamber in conjunction with a throttle valve when the throttle valve is opened, and injects fuel in the chamber into a suction passage through a discharge valve to accelerate the fuel. To make it smooth. Further, when the throttle valve is closed, the volume of the pump chamber is increased, and the pump chamber is sucked from the fuel chamber into the fuel pump chamber via the suction valve to prepare for the next acceleration. (June 53-22649
No.)

[0003]

[Problems to be Solved by the Invention] However, if the fuel in the pump chamber evaporates due to radiant heat or the like after being left for a long time and after the engine is stopped, the pump chamber becomes empty, and the accelerating fuel will be discharged at the next operation of the accelerating pump. It is not ejected, resulting in poor acceleration. In addition, the operation of the acceleration pump is required several times until the air in the pump chamber is completely exhausted and the function of the normal acceleration pump is restored. During that time, the discharge amount of the acceleration fuel is insufficient, and smooth acceleration is performed. Not.

SUMMARY OF THE INVENTION It is an object of the present invention to quickly exhaust air from a pump chamber of an acceleration pump, to reliably fill the pump chamber with fuel for acceleration, and to prevent poor acceleration due to fuel shortage.

[0006]

According to the present invention, a suction valve of an acceleration pump is set to normally open and closed by the discharge pressure of the acceleration pump, and one end is opened to a discharge passage upstream of the discharge valve. The other end is provided with an air discharge passage opening above the float chamber above the float chamber opening of the suction passage,
An on-off valve which is normally opened and closed by the discharge pressure of the acceleration pump is provided in the passage.

[0007]

When the acceleration pump is not operating, the suction valve and the on-off valve are opened, and the pump chamber is connected to the float chamber by the suction passage and the air discharge passage, so that the air generated in the pump chamber is discharged from the air discharge passage. Drained into the float chamber, the pump chamber is filled with fuel. Also, even when the float chamber itself becomes empty due to long-term storage, if fuel flows into the float chamber, fuel flows into the pump chamber from the suction passage via the suction valve, and at the same time, the air in the pump chamber Is discharged from the air discharge passage through the on-off valve to the float chamber, and the pump chamber and the discharge passage are quickly filled with fuel. Therefore, the pump chamber is always filled with fuel, and acceleration can be performed smoothly.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. 1 is a vaporizer. The main body 2 is provided with an intake passage 3 penetrating therethrough. The upstream side of the intake passage 3 is connected to an air cleaner (not shown), and the downstream side is connected to an intake port of an engine (not shown). In addition, this intake path 3
A venturi 6 is provided at the center of the Venturi, and a choke valve 7 is disposed upstream of the venturi 6 and a throttle valve 8 is disposed downstream thereof.

A float chamber 10 is provided below the intake path 3. The float chamber 10 has a main nozzle 12 having an upper end opening to the venturi 6 and a lower end communicating below the oil level in the float chamber 10 via a main jet 11.
Is arranged. Reference numeral 15 denotes a pump chamber of the acceleration pump device. The suction passage 17 of the pump chamber 15 is connected below the fuel oil level of the float chamber 10 via a suction valve 18, and is connected to the discharge passage 1.
9 is connected to an acceleration fuel nozzle 21 arranged in the intake passage 3 via a discharge valve 20.

A movable body 23 for increasing or decreasing the volume of the chamber 15 is provided in the pump chamber 15, and the movable body 23 is interlocked with the throttle valve 8 and the pump chamber is opened with the opening of the throttle valve 8. 15 are moved in the direction of decreasing the volume. As a result, the fuel in the pump chamber 15 is pressurized and the discharge valve 2
After passing through 0, the fuel is discharged from the acceleration fuel nozzle 21 to the intake passage 3. On the other hand, when the throttle valve 8 operates in the valve closing direction, the movable body 23 is moved in the direction of increasing the volume of the chamber 15 by the action of the spring 25 disposed in the pump chamber 15, and the suction passage 17 The fuel is sucked from the float chamber 10 via the suction valve 18.

The above is a conventionally well-known acceleration pump device. The present invention further provides the float chamber 10 and the pump chamber 15 by opening the suction valve 18 normally.
Are connected when the acceleration pump is not operating, and when the acceleration pump is operating, the suction valve 18 is closed by the discharge pressure of the fuel. One end is connected to the discharge passage 19 upstream of the discharge valve 20.
And an air discharge passage 27 having the other end opened at a position higher than the float chamber opening 17a of the suction passage 17 of the float chamber 10. The valve 27 is normally opened in this passage 27, and the discharge pressure at the time of operation of the acceleration pump is provided. An on-off valve 28 for closing the passage 27 is provided. The opening position of the on-off valve 28 on the float chamber 10 side may be either above the fuel oil level or below the oil level, but if it is opened below the oil level, the pump chamber 15 and the discharge It is possible to prevent fuel from entering the passage 19, which is more effective.

Next, the operation of the above configuration will be described.
When the acceleration pump is not operating, the suction valve 18 and the on-off valve 2
8 is opened, and the pump chamber 15 is
The air generated in the float chamber is discharged to the float chamber 10 through the air discharge path 27, and the pump chamber 15 is filled with fuel.

Next, when the throttle valve 8 is opened to accelerate the engine, the movable body 23 moves in a direction to reduce the volume of the pump chamber 15, and the fuel in the pump chamber 15 is pressurized. The pressurized fuel is opened from the accelerating fuel nozzle 21 to the intake passage 3 by opening the discharge valve 20.

When the float chamber 10 itself becomes empty due to long-term storage or the like, when fuel flows into the float chamber 10, the pump chamber 1 passes through the suction valve 18 and the suction passage 17.
5, the fuel in the pump chamber 15 is discharged from the passage 27 to the float chamber 10 through the on-off valve 28, and the pump chamber 15 and the discharge passage 19 are quickly filled with fuel. Therefore, the pump chamber 15 is always filled with fuel, and the performance of the acceleration pump can be sufficiently exhibited.

[0015]

According to the present invention, as described in detail above, the pump chamber communicates with the float chamber through the suction passage and the air discharge passage except during the operation of the acceleration pump, so that air accumulates in the pump chamber. Therefore, the fuel is always filled, and the supply of the accelerating fuel can be surely performed. In addition, even when the float chamber itself becomes empty, the fuel is filled while discharging air from the chamber to the pump chamber of the acceleration pump at the same time as the fuel flows into the float chamber. And the acceleration failure due to the shortage of the fuel stored in the pump chamber can be eliminated.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the vaporizer of the present invention.

[Description of Signs] 1 carburetor 3 intake path 10 float chamber 15 pump chamber 18 suction valve 20 discharge valve 21 acceleration fuel nozzle 23 movable body 27 air discharge passage 28 on-off valve

Claims (1)

(57) [Scope of request for utility model registration] 1. A pump chamber whose volume is increased or decreased by a movable body interlocking with a throttle valve, a suction passage connecting the pump chamber to a float chamber via a suction valve, and an accelerating fuel pump through a discharge valve. A discharge passage connected to a nozzle, wherein the suction valve is normally opened and set to be closed by the discharge pressure of the acceleration pump, and one end is opened to a discharge passage upstream of the discharge valve, and the other end is opened. Providing an air discharge passage opening to the float chamber above the float chamber opening of the suction passage, and an opening / closing valve which is normally opened and closed by the discharge pressure of the acceleration pump is provided in the passage. Vessel acceleration pump device.