JPS58150014A - L.o. supplying system in 2-cycle fuel injection engine - Google Patents

Abstract

PURPOSE:To obtain good lubrication to a fuel injection pump as well as to improve the durability thereof in a fuel supply system, in which a fuel like gasoline etc. is supplied separately with lubricating oil, by using the lubricating oil for lubricating a fuel injection pump before it is supplied to an engine. CONSTITUTION:Fuel is sent to a fuel injection pump 3 from a fuel tank 1 through a fuel supply pump 2. The fuel is pressurized here and sent to an engine 5 through a fuel injection pipe 4. On the other hand, lubricating oil is supplied to the engine 5 via the fuel injection pump 3 from an oil tank 6 by means of an oil pump 7. To this purpose, a plunger 8 of the fuel injection pump 3 is provided with a collar-shaped passage 12 that allows the lubricating oil to pass, at the lower part of the fuel pressurizing part so that the lubricating oil enters from an inlet 13, passes the passage 12, and goes out from an outlet 14, regardless of the vertical and rotational position of the plunger 8. An inlet 13 and outlet 14 for the lubricating oil are connected to the oil tank 6 and oil pump 7, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a lubricating oil supply system for a 2t cycle fuel injection system.

The purpose of the present invention is to improve the lubrication of the fuel pressurizing mechanism parts such as the plunger that sends out the injected fuel in a two-cycle fuel injection engine, prevent leakage of fuel from the parts to the outside, and improve the durability of the plunger. The aim is to improve sexuality.

Conventionally, when injecting low-viscosity fuels such as gasoline, alcohol, and kerosene, the plunger often seizes due to lack of lubrication, and to prevent this, increasing the clearance between the plunger and plunger barrel causes more leakage. However, various methods have been proposed for fuel injection dump lubrication in four-site gasoline injection engines and have already been put into practical use. . This kind of method is 2
Of course, it can also be used during cycle fuel injection, but this method takes advantage of the fact that two-stroke engines are dry sump systems, and is also unique in that it can be easily implemented in two-stroke engines that perform separate lubrication. - This method is particularly effective when using low-viscosity fuels such as gasoline, alcohol, and kerosene, improving lubrication, preventing fuel leakage, and increasing engine thermal efficiency. The embodiment will be explained with the help of diagrams. In WJl and FIG. 2, fuel is supplied from the fuel tank (1) by the fuel supply pump (positive) to the fuel injection pump (3), where it is pressurized and then passed through the fuel injection pipe (4). In addition, lubricating oil is sent to the engine (in Figure 1) from the oil tank (6) through the fuel injection pump (3) to the oil pump (
is supplied to the engine (5) by η. In the case of Fig. 2, the lubricating oil comes out of the oil tank (6) and first goes to the oil pump (6).
7> is sent to the fuel injection pump (5), where it lubricates the plunger and then sent to the engine (5). In both the systems shown in Figures 1 and 2, a filter or the like may be placed in the middle of the fuel and lubricating oil supply system. Figure 3 shows the plunger lubrication structure of the fuel injection pump (3) in Figures 1 and 2. This is an example. This inversion refers to the plunger of the Botsushiou fuel injection pump. (8) is the plunger that moves up and down inside the plunger barrel (9), and the upper part is the normal fuel pressurizing part, and (10) is the fuel intake. Hole, (11
) is the discharge hole. There is a collar-shaped (12) at the bottom of the fuel pressurizing part of the plunger (8) to allow lubricating oil to pass through, and the lubricating oil enters from the inlet (13) regardless of the vertical or rotational position of the plunger (12). ) and exit (
14). Lubricating oil inlet (13)
and the outlet (14) are respectively oil tanks (in the case of Fig. 1).
6) and the oil pump (7), or in the case of FIG. 2, the oil pump (7) and the engine (5), respectively.

In this way, sufficient lubricating oil is supplied between the plunger and the barrel of the fuel injection pump, and a portion of it mixes with the fuel leaking from the top of the plunger, lubricating that part and reducing the leakage of this fuel. do. Furthermore, the leaked fuel is ultimately supplied to the engine together with the III lubricant oil and is combusted, thereby contributing to the engine output. Also, from the clearance of the puttenger and barrel,
Lubricating oil may enter the fuel system, and is sent along with the fuel to the fuel injection nozzle, where it is injected into the engine while lubricating the nozzle. Naturally, in this case, it does not matter where the fuel is injected or where the lubricating oil is supplied in the engine.

In the case of the present invention, there are no restrictions on the installation position and drive method of the oil pump; it can be installed on the engine body and driven by the crankshaft, or it can be installed on the fuel injection pump and driven by the mechanical shaft. - If so, an electric oil pump or the like may be used.

Furthermore, oil can be easily discharged by making the diameters of the lubricating oil passage portions of the buttenger or plunger barrel shown in FIG. 1 different in steps, and this can also be used as an oil pump. In this case, it is also possible to easily create a structure in which the oil discharge amount is uniquely determined in accordance with the fuel discharge amount.

Integrating the fuel discharge plunger and the oil pump into one unit has the advantage of simplifying the structure and lowering the price.

Further, the application of this method to a fuel injection pump using a plunger and a barrel is just one example, and it goes without saying that it can be applied to other fuel injection pumps as well.

As described above, according to the present invention, low viscosity fuel is used.
Even in cycle fuel injection engines, this technology improves the lubrication of the fuel injection pump, prevents leakage of fuel to the outside, and improves the durability of the pump, making it possible to maintain smooth engine operation and thermal efficiency. .

[Brief explanation of drawings]

1 and 2 are fuel and lubricant supply system diagrams showing an embodiment of the present invention. FIG. 3 shows an example of the structure of the plunger, plunger, and rear part of the fuel injection pump used in this method.

Claims (1)

[Claims] (1) In a two-cycle engine in which fuel such as gasoline is supplied by an injection pump and an injection nozzle, and lubricating oil is supplied separately from this fuel, the fuel is injected before this lubricating oil is supplied to the engine. A lubricating oil supply method in which the oil is used to lubricate the fuel injection pump such as the plunger of the pump, and then the oil is sent to the engine and used to lubricate the engine. (No. In the preceding paragraph "Claims" (1), lubricating oil supply that is used as an oil dump by modifying a part of the fuel discharge element (for example, the plunger part of the L fuel injection dump) to have the function of an oil pump. method.