JPH04255556A - Starter device for two-cycle engine - Google Patents

Abstract

PURPOSE:To promptly and easily supply starting fuel in a 2-cycle engine even after the engine is left as it is for a long time. CONSTITUTION:In the case of a starter device for a 2-cycle engine provided with a manually-operated starting fuel pump 32 for supplying starting fuel in a fuel supply route of the engine 10, a starting fuel passage 31, connected to a fuel tank 12 to bypass a float chamber 17 of a carburetor 16, is provided so as to supply fuel to the starting fuel pump 32 from this starting fuel passage 31.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a starting device for a two-stroke engine.

0002

2. Description of the Related Art Conventionally, a starting device for a two-cycle engine has been proposed as described in Japanese Patent Application Laid-Open No. 56-151241. This prior art supplies fuel from the float chamber of the carburetor to the starting fuel pump.

0003

[Problems to be Solved by the Invention] However, in the prior art, when starting after being left unused for a long time, it is necessary to operate the starting fuel pump several times in order to bleed air from the starting fuel passage and the starting fuel pump chamber. , lacks quick and easy startup.

SUMMARY OF THE INVENTION An object of the present invention is to quickly and easily supply starting fuel to a two-stroke engine even after the engine has been left unused for a long time.

[0005]

[Means for Solving the Problems] The present invention provides a two-cycle engine starting device equipped with a manual starting fuel pump that supplies starting fuel to a fuel supply path of the engine. A starting fuel passage is provided that bypasses the starting fuel pump, and fuel is supplied from this starting fuel passage to the starting fuel pump.

[0006]

According to the present invention, fuel is supplied to the starter fuel pump from the starter fuel passage which bypasses the float chamber of the carburetor. Therefore, even when starting after being left unused for a long time, the pump does not require air movement to bleed air from the float chamber, and can quickly and easily supply starting fuel.

[0007]

[Embodiment] Fig. 1 is a fuel supply system diagram showing one embodiment of the present invention, Fig. 2 is a schematic diagram showing an engine, Fig. 3 is a sectional view showing the fuel drain pipe discharge port of Fig. 2, and Fig. 4 is a diagram showing the fuel drain pipe discharge port of Fig. 2. FIG. 5 is a cross-sectional view showing a fuel drain pipe suction port, and FIG. 5 is a schematic diagram showing an example of a starting fuel pump.

As shown in FIG. 1, the main fuel passage 11 for the two-stroke outboard engine 10 runs from a fuel tank 12, through a primary pump 13, a filter 14, and a fuel pump 15, to a float chamber of a carburetor 16. It extends to 17.

The engine 10 is equipped with a recoil starter (not shown) and can be started manually.

[0010] Furthermore, the engine 10 is of a horizontal cylinder type,
The left and right banks are equipped with two cylinders each, upper and lower.

[0011]Then, each of the left and right banks is shown in FIGS.
As shown in FIG. 4, a fuel drain pipe 18 has a suction port at the bottom of the reed valve in the crank chamber of the upper cylinder and a discharge port at the cylinder side wall of the lower cylinder, and a suction port at the bottom of the reed valve in the crank chamber of the lower cylinder. A fuel drain pipe 19 is provided which is open and has a discharge port in the cylinder side wall of the upper cylinder. In FIG. 2, 21 is a reed valve, and 22 is a piston.

At this time, the pistons 22 of each cylinder of the engine 10 are connected to each drain pipe 18, 19 at 90 degree intervals in the order of, for example, the left bank upper cylinder, the right bank upper cylinder, the left bank lower cylinder, and the right bank lower cylinder. Open the outlet. This results in
Fuel is discharged from the fuel reservoir in the crank chamber of one cylinder to which the drain pipes 18 and 19 are connected to the cylinder side wall of the other cylinder.

However, since the engine 10 is a recoil starter as described above, the starting engine speed is low, and as a result, there is a lack of fuel suction negative pressure to suck fuel from the carburetor side to the combustion chamber. In order to compensate for this and improve starting performance, the following starting device is provided.

That is, the engine 10 is provided with a starting fuel passage 31 that is connected to the fuel tank 12 and bypasses the float chamber 17 of the carburetor 16, and fuel is supplied from the starting fuel passage 31 to the starting fuel pump 32. ing. The discharge passage 33 of the starting fuel pump 32 is connected to the drain pipe 1 described above.
8.

The starting fuel passage 31 has a starting end in the main fuel passage 11 on the upstream side of the connection part of the carburetor 16 to the float chamber 17 and further between the primary pump 13 and the fuel pump 15.

[0016] Here, the starting fuel pump 32 is, for example,
It can be configured manually as shown in FIG. That is, the pump 32 is provided with a diaphragm 43 that defines a pump chamber 42 within a housing 41, and a valve body 44 provided at the center of the diaphragm 43 can be moved into and out of contact with a valve seat 45 provided at the suction port 41A of the housing 41. The valve body 44 is separated from the valve seat 45 by pulling the manual knob 46, and the return force of the spring 47 brings the valve body 44 into contact with the valve seat 45. Therefore, in the pump 32, fuel can be sucked in from the suction port 41A by pulling the manual knob 46, and fuel can be discharged from the discharge port 41B by the return force of the spring 47.

That is, in the engine 10, (1)
The primary pump 13 fills the starting fuel passage 31 from the fuel tank 12 with fuel, and (2) the starting fuel pump 32
The engine can be started by operating the manual knob 46 to supply starting fuel from the drain pipe 18 to each cylinder of the engine 10, and (3) activating the recoil starter.

However, in the engine 10, the starting fuel pump 32 that operates in conjunction with the recoil starter is used, (1) the primary pump 13 fills the starting fuel passage 31 from the fuel tank 12, and (2) ) The starting fuel pump 32 that is linked to the recoil starter is operated, thereby supplying starting fuel to each cylinder of the engine 10 from the drain pipe 18, and the starting can be completed at the same time, or (1) Starting that is linked to the recoil starter. The fuel pump 32 is operated and the starting fuel passage 3 is removed from the fuel tank 12.
It is also possible to supply the starting fuel sucked through the engine 1 through the drain pipe 18 to each cylinder of the engine 10 and complete the starting at the same time.

Next, the operation of the above embodiment will be explained.

■ The starting fuel pump 32 is connected to the starting fuel passage 31 bypassing the float chamber 17 of the carburetor 16.
fueled to. Therefore, even when the pump 32 is started after being left unused for a long period of time, the pump 32 does not require pneumatic movement to bleed air from the starting fuel passage and the starting pump chamber, and can quickly and easily supply starting fuel.

[0021] Since the starting fuel passage 31 is connected to the upstream side of the fuel pump 15, fuel from the primary pump 13 can be smoothly introduced into the pump 32 without any resistance from the fuel pump 15, making starting easier.

■The discharge passage 33 of the starting fuel pump 32,
Of the drain pipes 18 and 19, the drain pipe 18, which has a discharge port open on the lower cylinder side, is connected to the drain pipe 18, so that the fuel from the pump 32 can be easily guided to the cylinder side by its own weight, and starting is facilitated.

However, in carrying out the present invention, the discharge passage of the starting fuel pump may be communicated with any of the fuel supply paths of the engine.

[0024]

As described above, according to the present invention, starting fuel can be quickly and easily supplied to a two-stroke engine even after it has been left unused for a long time.

[Brief explanation of the drawing]

FIG. 1 is a fuel supply system diagram showing one embodiment of the present invention.

FIG. 2 is a schematic diagram showing an engine.

FIG. 3 is a sectional view showing the fuel drain pipe outlet of FIG. 2;

FIG. 4 is a sectional view showing the fuel drain pipe suction port of FIG. 2;

FIG. 5 is a schematic diagram showing an example of a starting fuel pump.

[Explanation of symbols]

10 Engine 12 Fuel tank 16 Vaporizer 17 Float chamber 31 Starting fuel passage 32 Start fuel pump

Claims (1)

[Claims] Claim 1: A starting device for a two-cycle engine equipped with a manual starting fuel pump that supplies starting fuel to a fuel supply path of the engine, including a starting fuel passage that is connected to a fuel tank and bypasses a float chamber of a carburetor. A starting device for a two-stroke engine, characterized in that it is configured to supply fuel from the starting fuel passage to a starting fuel pump.