JPH02125914A - Intake passage structure of two cycle internal combustion engine - Google Patents

Abstract

PURPOSE:To suppress the flowing resistance of intake air so as to increase output by setting the direction of an intake die flow through a first intake passage leading from an air intake port to an intake air plate and the direction of the same flow through a second air intake passage leading from the plate the crank case to be nearly same. CONSTITUTION:A reed valve 6 installed on an intake air plate 14 is arranged on each of intake passage 4 communicating respectively to a plurality of crank cases 2 provided on an engine body 1, and each intake passage 12 is formed on the reed valve 6 side of the intake air plate 14. Further, a throttle body 30 is installed on the plate 14, and an intake passage 28 is formed between a plurality of injectors 16 mounted on the throttle body 30, while the throttle valve 30 is arranged in the intake passage 28. Moreover, the intake passages 12 die formed in the injecting direction of the injector 16, while provided in the positioning relation to hold the intake passage 28 therebetween, so that air passing through the intake passage 28 branchs away in two directions so as to flow in respective intake passages 12.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a two-recycle internal combustion engine having an injector (
This article relates to an improvement in the structure of the air intake path from J to the crankcase, which takes in air from outside the main body of the engine (hereinafter also referred to as the engine).

(Prior Art) Metals are often used in electrical system members such as injectors that supply fuel to engines, connectors for controlling the injection of injectors, etc. In a corrosive environment F such as a marine atmosphere or bad weather, the metal parts of these electrical system members, especially terminals and contacts, will progress to corrosion and deterioration, and the engine may not operate properly due to poor continuity or disconnections. Therefore, in order to protect the injector lid and injector connector that supply fuel to the 2-recycle engine from corrosive environments such as the marine environment, the following measures are taken. A device has been proposed.

In other words, the I
In this space, when the engine is running, the area where the inductor and its connector are located is filled with scum that is not affected by the intake air flow. After passing the air through the throttle valve, the intake flow is
Turn, make a sharp change in direction, and let the crankshaft flow into the crankshaft c5t! 470
(Refer to 2202), (Problems to be Solved by the Invention) However, in the proposal of the above-mentioned prior art, due to a large direction change such as a U-turn of the intake flow in the intake passage, even if the throttle valve is fully open, the This has the problem that the intake air resistance is large, which obstructs the intake air from flowing into the engine, and the maximum output of the engine is suppressed.

Therefore, in order to solve the above-mentioned problems, the present invention takes up the problem of providing an intake passage structure for a two-stroke engine that effectively increases the engine output and does not suppress the maximum output.

(Means for Solving the Problems) In other words, 15, the above problem includes: an air intake port that communicates with the outside of the engine body and takes in air; a first intake path from the air intake L to the intake air plate; a second intake passage leading to the crankcase of the intake air plate;
In the 21-cycle internal combustion engine having an injector that supplies fuel to the crankcase, the direction of the intake air flowing through the first intake passage and the direction of the intake air flowing through the second intake passage are substantially the same direction. This problem is solved by the intake passage structure of a recycle internal combustion engine.

(Function) By adopting the configuration described in 1, the present invention allows intake air to flow smoothly into the engine, and the inflow resistance does not become too large, so that the engine output can be effectively increased, and the maximum output can be suppressed. Never.

(Example) An example according to the present invention will be described with reference to FIGS. 1 to 3.

FIG. 1 is a longitudinal cross-sectional view of a main part of an embodiment of the present invention in a three-cylinder engine equipped with an injector.The intake system is a piston reed valve system.

The engine body 1 is provided with three crankcases 2. An intake passage 4 communicates with each crankcase 2,
A reed pal 16 is attached to each intake passage 4. However, for the sake of clarity, Figure 1 shows the rightmost intake passage 4.
Only the lead pulse 16 is shown, and the others are not shown. Each reed valve 6 is composed of a reed 8 and a stopper 10 for regulating its opening degree, and allows the mixture of air and fuel to flow into the crankcase 2 and prohibits it from flowing out from the crankcase 2. The crankcase 2 communicates with a combustion chamber (not shown) through an intake passage (not shown), and the air-fuel mixture sucked into the crankcase 2 is further sent to the combustion chamber.

The reed valve 6 is attached to the C intake air plate 14 via a gasket 60 and the like.

An intake passage 12 is formed on the intake air plate 14 on the reed valve 6 side. Intake air plate 1
4 through the gasket 62.
The three injectors 16 are attached to the throttle body 30, which is equipped with a rubber ring 1.
It is accommodated via 9.20 etc. Furthermore, an intake passage 28 is formed between the injectors 16 and 16, and a throttle valve 38 is rotatable therein to adjust the amount of intake air.Intake air plate 14 The side intake passage 12 is formed in the injection direction of the injector 16, and is positioned so as to sandwich the intake passage 28 of the cylinder body 30. Therefore, the air that has passed through the intake passage 28 is The air is divided into two directions and flows into the intake passage 12.

The throttle body 30 has a cover 32 and a gasket 64.
It is installed through. The accommodation chamber 22 that accommodates the injector 16 includes a cover 32 and a throttle body 3.
0, etc., and protects the injector 16 and its electrical appliances from moisture, salt, etc. in the outside air.

Although the A-A cross section of the throttle body 30 in FIG. 1 is not shown in FIG.
In addition to the main body of the connector 6, a connecting wire 50 that is electrically connected to the connector 7 and the E CjJ 36, etc. are accommodated. Further, a socket 21 is provided at a position where the connecting wire 50 exits the housing chamber 22 to protect the connecting wire 50 and to isolate the inside of the housing chamber 22 from the outside of the engine main body.

A fuel passage 26 for supplying fuel to the injector 16 is formed in the cover 32, and one end thereof is connected to the fuel inlet 25.
A 3-pressure regulator 24, which is connected to a fuel FIJ-f chamber 24a of a pre-social regulator 24 whose other end will be described later, is connected to a fuel pressure chamber 24a and a base i If which introduces intake pressure. 24b, etc., and adjusts the fuel pressure in the fuel Fl pressure chamber 24a so that the pressure difference between the fuel flow chamber 24a and the reference pressure chamber 24b is constant. Furthermore, the cover 32 has two air intake ports 34 for taking in air.
is open in places. The air flowing in from the air intake port 34 flows almost straight into the intake passage 28 of the throttle body 30 without significantly changing its flow direction. A control device (hereinafter referred to as ECU) 36 is installed. The positional relationship between the cover 32 and the cover 32 is shown in FIG. The inlet 34° 34 is covered by the ECU 36 and has a structure that prevents splashes of muddy water, rainwater, etc. from entering.

Further, the manner in which the E Cj, J 36 covers the air intakes [131, 34 is not limited to the manner shown in FIG. 3, but may be in any manner (as long as it is difficult for intruders other than fresh air from outside the engine to enter).

In addition, the cover covering the air intake port 34.34 is F CU 3
It is not limited to 6.

Next, the operation of this embodiment will be explained with reference mainly to FIG.

When the engine is operating and the piston (not shown) is in the first stroke (intake/Jl; contraction stroke), the inside of the crankcase 2 becomes negative 11, and the intake air flow 40 flows into the air intake port 34 of the cover 32.
occurs. Furthermore, the air taken into the engine body 1 becomes an intake air flow 42 inside the cover 32. The amount of intake air passing through the intake passage 28 is adjusted by the opening degree of the throttle valve 38, and the intake air flow in the direction 27J is 4'1.46.
, and the crankcase 2 passes through the intake passage 12, respectively.
is inhaled. Furthermore, fuel is injected toward the intake passage 12 by the injector 16, and the intake air and fuel are mixed.

When the piston enters a downward stroke (explosion/scavenging stroke) and the piston moves down F, the effective negative pressure in the crankcase 2 for intake tends to decrease. At this time, the reed valve 6 is slightly open until just before the piston descends and τ scavenging begins through the scavenging holes provided in the combustion chamber (not shown), and the air-fuel mixture sucked into the crankcase 2 is pushed back. Sometimes (blowback phenomenon). However, the intake passage 12 and the intake passage 28 are located opposite each other as shown in the figure, and the air-fuel mixture does not leak from the throttle valve 38 to the outside of the engine body 1.

The cover 32 also includes an ECU 36 that covers the air intake port 34.
is installed, it is possible to prevent moisture, salt, etc. from entering from the outside of the engine body 1 as much as possible.

As a result of the above 1-, the engine output corresponding to the opening degree of the throttle valve 38 is efficiently realized, and the maximum output of the engine is not suppressed.

(Effects of the Invention) In the present invention, in a two-cycle engine having an indicator I, the intake air flow flowing through the first intake passage leading to the air plate and the intake air flow flowing through the first air intake passage leading to the air plate and the classic・Due to the structure of the intake passage of a two-stroke internal combustion engine in which the intake air flow through the second intake passage leading to the space is almost in the same direction, the maximum output of the engine can be suppressed by minimizing the intake air inflow resistance. It has the effect that there is no

[Brief explanation of drawings]

1 to 3 show an embodiment according to the present invention, FIG. 1 is a general longitudinal cross-sectional view of the embodiment, FIG. 2 is a cross-sectional view taken along the line A-A in FIG. 1, and FIG. FIG. 3 is a positional relationship diagram between the cover and the ECU. 1...Engine body 2...Crank case 6...Reed pulp 4.12.28...Intake path 14...Index 7 plate 16...Injector 30...Throttle body 32... Cover 34... Air intake port 36... ECLI 38... S1'' valve

Claims (1)

[Claims] An air intake port that communicates with the outside of the engine body and takes in air;
A first pipe extending from the air intake port to the intake air plate.
In a two-stroke internal combustion engine having an intake passage, a second intake passage extending from the intake air plate to the crankcase, and an injector for supplying fuel to the crankcase, the direction of the intake air flowing through the first intake passage and the An intake passage structure for a two-stroke internal combustion engine in which the direction of the intake air flowing through the second intake passage is substantially the same direction.